MOST NOTEWORTHY: P.F. Chang's, ViroPharma and CSX Corp were today's noteworthy upgrades:

• Jefferies upgraded shares of P.F. Chang's (NASDAQ: PFCB) to Buy from Hold to reflect the company's capital preservation focus, which they believe will drive a best-in-class free cash flow yield in 2009. Despite upgrading shares, Jefferies lowered their target price to $28 from $31.
  
• Thomas Weisel raised ViroPharma (NASDAQ: VPHM) to Overweight from Market Weight on valuation as they believe the sell-off on the Lev Pharmaceuticals (LEVP) acquisition is unwarranted. The firm raised their target price to $15 from $10.
  
• Merrill upgraded CSX Corp. (NYSE: CSX) to Buy from Neutral based on valuation and improved results.

OTHER UPGRADES:

• Borg-Warner (NYSE: BWA) was upgraded to Outperform from Neutral at Baird.
  
• Credit Suiise raised Walgreen (NYSE: WAG) to Outperform from Neutral.
  
• SunTrust upgraded Arena Resources (NYSE: ARD), Bill Barrett (NYSE: BBG) and Concho Resources (NYSE: CXO) to Buy from Neutral.

MOST NOTEWORTHY: Jabil Circuit, Aircastle, Genesis Lease and P.F. Chang's were today's noteworthy downgrades:

• JP Morgan downgraded shares of Jabil Circuit (NYSE: JBL) to Underweight from Overweight following the lower-than-expected guidance, as they believe the company is seeing end market weakness in most of its markets. Shares were also downgraded at Thomas Weisel to Market Weight from Overweight and at Credit Suisse to Neutral from Outperform following the disappointing guidance.
  
• JP Morgan also downgraded shares of Aircastle (NYSE: AYR) and Genesis Lease (GLS) to Neutral from Overweight to reflect the continued credit and equity market challenges faced by both companies.
  
• Friedman Billings downgraded shares of P.F. Chang's (NASDAQ: PFCB) to Underperform from Market Perform as they believe 2008 will be a challenging year for all casual dining restaurant companies and that the valuation is expensive at current levels.

OTHER DOWNGRADES:

• Goldman added Foundation Coal (NYSE: FCL) to its Conviction Sell List.
  
• Collins Stewart cut SiRF Technology (NASDAQ: SIRF) to Hold from Buy.
  
• Elan Corp (NYSE: ELN) was downgraded to Sell from Hold at Canaccord Adams.

Georges Yared notes in his insightful post about Amazon.com, Inc.'s (NASDAQ: AMZN):

Amazon has been what Wall Streeters call a "stalled-story". That means the company took most of 2004-2006 to build very expensive infrastructure and spent heavily on heavy marketing expenses to acquire customers. This spending spree took the winds out of Amazon's sails for those three years. Earnings growth, visibility and momentum suffered as did the share price.

Throughout the rest of the post, Georges explains the very interesting growth long-term growth story in Amazon, as he responds to my recent post about the short-term price action I expect in Amazon.

I believe this entire situation is a perfect example of two things: 1) How a mindset going into a position can affect what the investor is looking for; and 2) How two different people, with different perspectives, can potentially be right about a stock.

I've noted the different mindsets between going into a trade and going into an investment before on BloggingStocks. Something like Earthlink (NASDAQ: ELNK) would be an investment, while something like PF Chang's (NASDAQ: PFCB) or Google (NASDAQ: GOOG), would be pure trades, meaning there's no intent to hold the stock. PF Chang's trade I've discusses was event-driven with the belief that the company would cut guidance, which it did. Google's was a sentiment play due to the belief that stockholders would get nervous with the company's performance, and so far it seems they have.

It's important that people remember this concept because oftentimes when I have a thought on a trade it could be different from my long-term view of a stock.

MOST NOTEWORTHY: Advantest (ATE), RightNow Technologies (RNOW), Mattson Technology (MTSN), Akamai Technologies (AKAM) and P.F. Chang's (PFCB) were today's noteworthy downgrades:

• Matrix downgraded Advantest (NYSE: ATE) to Strong Sell from Hold; the firm doesn't expect Advantest's profits to improve in the near-term after chip makers indicated they plan to cut capital spending.

• RightNow Technologies (NASDAQ: RNOW) was cut to Sector Perform from Outperform at Pacific Crest to reflect the company's poor execution.

• Mattson Technology (NASDAQ: MTSN) was downgraded to Sell from Buy at American Technology; The firm said Q2 results were strong but bookings and gross margin outlook were weaker due to memory spending weakness.

• Credit Suisse downgraded P.F. Chang's (NASDAQ: PFCB) to Market Weight from Overweight at Thomas Wiesel to reflect below plan new store performance for the third consecutive year at Pei Wei...

OTHER DOWNGRADES:

• Citigroup cut Taiwan Semi (NYSE: TSM) to Hold from Buy.

• Merriman downgraded Fuel Tech (NASDAQ: FTEK) to Neutral from Buy.

• Bear Stearns cut Hess Corp (NYSE: HES) to Peer Perform from Outperform.

• Goldman Sachs removed Merrill Lynch (NYSE: MER) from its Conviction Buy list.

Analyst summaries provided by TheFlyOnTheWall.com (subscription required).

Shares of Panera Bread Company (NASDAQ: PNRA) have pulled back since the company reported earnings in early April. The firm posted first-quarter earnings that were at the low end of its previous target of $0.47 to $0.50 per share -- that represented a slight discount to consensus analyst expectations. This announcement, coupled with a similar warning from PF Chang's China Bistro (NASDAQ: PFCB), sparked fears that a slowdown in consumer spending is starting to hit the fast-casual restaurant chains.

But Panera's problems are at least partly due to geography and weather. Specifically, PNRA is based in St. Louis and has a high concentration of locations in the Midwest. This region of the country has been hit with particularly severe winter weather on several occasions this year, and such storms drastically slow business.

This inclement weather was particularly problematic because of Panera's policy of using fresh dough for its breads and pizzas. Basically, this dough must be made fresh each morning and tossed out at the end of each day. Lighter store traffic leads to lost revenues and higher raw ingredients costs.

However, I believe the worst possible news is already priced into the stock. Even based on lowered estimates, PNRA is trading at roughly 20 times forward earnings, a slight discount to its +24% long-term growth rate. That's cheap for a high-quality growth stock like PNRA.

To see more analysis from Paul Tracy, visit www.streetauthority.com

Other than the occasional (okay, fairly frequent) lunchtime or late-night trek to Taco Bell -- a unit of Yum! Brands (NYSE: YUM) -- I'm generally not a huge fan of chain restaurants. Most are very good at what they do, but when I'm dining out with friends or family, I typically prefer something off the beaten path.

One exception to this, however, is the upscale Asian dining spot P.F. Chang's China Bistro (NASDAQ: PFCB). If I may suggest, the steamed dumplings and garlic noodles border on culinary perfection.

PFCB shouldn't need much of a PR blitz from me, however; the waits are always long, any day of the week, and the reviews are generally of the rave variety. And yet, March same-store sales dropped 3.0% at the eatery's benchmark China Bistro locations and edged 0.5% higher at its Pei Wei restaurants. For the quarter, China Bistro same-store sales dropped 2.5% while Pei Wei sales rose 0.5%. Total revenue for the quarter ended April 1 rose to $264.4 million, up 15.6% from year-earlier levels but below analysts' expectations of $268.2 million.

On the heels of this news, PFCB shares have dropped more than 5%, dipping back below their 10-day and 20-day moving averages.

Beth Gaston Moon is an analyst at Schaeffer's Investment Research.

MOST NOTEWORTHY: Endo Pharmaceuticals Holdings Inc (ENDP) and Coldwater Creek (CWTR) were today's most notable initiations:

• First Albany initiated Endo Pharmaceuticals Holdings Inc (NASDAQ: ENDP) with a Strong Buy rating and $41.25 target; the firm believes the company's strong balance sheet can be used to strengthen the pipeline through the acquisition of product rights or companies.

• Thomas Weisel started Coldwater Creek Inc (NASDQ: CWTR) with an Underperform rating based on the fourth-quarter miss, and believes appreciation could be limited here.

OTHER INITIATIONS:

• Yamana Gold Inc (NYSE: AUY) was initiated with a Sector Performer rating and $20 target at CIBC, explaining that Yamana's production profile is expected to expand by 150% in the next two years, making it one of the fastest-growing gold companies in North America.

• Oppenheimer considers PF Chang's China Bistro's (NASDAQ: PFCB) valuation attractive and started the restaurant chain with a Buy rating and $53 target.

Analyst summaries provided by TheFlyOnTheWall.com (subscription required).

MOST NOTEWORTHY: Wal-Mart (WMT) and Motorola (MOT) were the most notable downgrades this morning.

• Goldman Sachs downgraded Wal-Mart Stores Inc. (NYSE: WMT) to Neutral from Buy; citing weaker sales and expected heavy markdowns.

• Credit Suisse removed shares of Motorola Inc. (NYSE: MOT) from their Focus List.

OTHER DOWNGRADES:

• Bear Stearns downgraded the Restaurant Sector to Market Weight from Overweight, citing valuations and softening fundamentals. In addition, Applebee's International Inc. (NASDAQ: APPB) and P.F. Chang's China Bistro Inc. (NASDAQ: PFCB) were both downgraded to Underperform from Peer Perform.

• Following the lower-than-expected Q4 guidance, Morgan Keegan downgraded shares of Tellabs Inc. (NASDAQ: TLAB) to Market Perform from Outperform, as they do not expect a quick earnings recovery.

• Ensco International Inc. (NYSE: ESV) was downgraded to Underweight from Equal Weight at JP Morgan; the firm says there is growth risk to the global jackup market including overcapacity in early 2008.

Analyst summaries provided by TheFlyOnTheWall.com (subscription required).

MOST NOTEWORTHY: Specific restaurants and Autodesk (ADSK) top today's list of initiations.

• Robert W. Baird initiated coverage of Starbucks Corp. (NASDAQ:SBUX), Panera Bread Co. (NASDAQ:PNRA), Chipotle Mexican Grill, Inc. (NYSE:CMG) and Texas Roadhouse, Inc. (NASDAQ:TXRH) with Outperform ratings and P. F. Chang's China Bistro Inc (NASDAQ:PFCB) and Rare Hospitality International, Inc. (NASDAQ:RARE) with Neutral ratings.
• American Tech initiated Autodesk , Inc. (NASDAQ:ADSK) with a Buy rating and $12 target. The firm expects to see meaningful upside to 2008 consensus estimates and recommends investors to buy the stock on any pullback following Thursday's results.

OTHER INITIATIONS:

• Soleil initiated Openwave Systems, Inc. (NASDAQ:OPWV) with a Hold rating, citing unlikely outperformance due to their maturing product line and consolidating customer base.
• The Bank of America initiated F5 Networks, Inc. (NASDAQ:FFIV) with a Buy and $90 target. The firm said checks in the enterprise segment have been positive. In addition, Soleil said the company will soon enter a major product cycle with four launches.

Analyst summaries provided by TheFlyOnTheWall.com (subscription required).