MOST NOTEWORTHY: CBS Corp., Thornburg Mortgage and DiamondRock Hospitality were among today's noteworthy downgrades:

• CBS Corp. (NYSE: CBS) was downgraded to Market Perform from Outperform at Wachovia, citing the weak ad environment and potential M&A strategy to acquire growth, which will limit upside near-term.
  
• Thornburg Mortgage (NYSE: TMA) was downgraded to Underperform from Outperform at Friedman Billings, which said the recent capital raise and related transactions result in 95% dilution, and questions how shares will trade when 2.9B restricted common shares are registered and start trading in mid- May.
  
• DiamondRock Hospitality (NYSE: DRH) was downgraded to Neutral from Outperform at Baird following the company's reduced guidance.

OTHER DOWNGRADES:

• Savvis Inc. (NASDAQ: SVVS) was downgraded to Equal Weight from Overweight at Lehman following the company's Q1 report and guidance.
  
• Memc Electronic Materials (NYSE: WFR) was downgraded to Neutral from Overweight at J.P. Morgan, who cited high Street expectations and a very tight capacity expansion schedule over the next few quarters.

Here are some highlights from this past week's earnings coverage from BloggingStocks:

• Amazon.com Inc. (NASDAQ: AMZN) profits rose 30%, easily beating analysts' expectations.
• AMETEK Inc. (NYSE: AME) beat Q1 estimates on global strength and recent acquisitions.
• Apple Inc. (NASDAQ: AAPL) easily beat Q2 expectations but offered a weak outlook.
• AT&T Inc. (NYSE: T) posted strong Q1 results thanks to the popularity of the iPhone.
• Baidu.com Inc. (NASDAQ: BIDU) beat earnings and saw an upgrade from Citigroup Inc. (NYSE: C).
• Broadcom Corp. (NASDAQ: BRCM) Q1 profit soared, and it raised its guidance.
• Cymer Inc. (NASDAQ: CYMI) beat Q1 estimates and announced a share million buyback program.
• Electronic Data Systems Inc. (NYSE: EDS) posted Q1 profits on cost cutting and new contracts.
• EMC Corp. (NYSE: EMC) Q1 earnings fell on on acquisition-related charges.
• Hexcel Corp. (NYSE: HXL) beat Q1 estimates on increased commercial aerospace sales.
• Huaneng Power ADS (NYSE: HNP) earnings plunged on coal prices, but the stock went higher.
• Level 3 Communications Inc. (NASDAQ: LVLT) narrowed its loss on higher sales of networking services.
• McAfee Inc. (NYSE: MFE) Q1 profit plunged on product development and marketing costs.
• MEMC Electronic Materials Inc. (NYSE: WFR) missed analysts' estimates for the first quarter.
• Microsoft Corp. (NASDAQ: MSFT) beat earnings expectations and raised its full-year guidance.
• Netflix Inc. (NASDAQ: NFLX) profit soared in the first quarter on increase in subscriptions.
• Nintendo Co. (OTC: NTDOY) posted record results due to the popularity of the Wii system.

This market is tough. Pros and novices alike are having a tough time. Particularly in a down market, a market commentators like to call a ""stock picker's market," I find it illustrative to dig deeper into the holdings of those special professional money managers that have found a way to make a go of it.

Take the CGM Focus (CGMFX) fund. This fund consistently shows up at the top of 1-year, 3-year, and multi-year best performers. CGM Focus has returned on average 37% per year for the past five years. While this is absolutely no guarantee that it will continue to perform like this, fund manager Chuck Heebner seems to have the special sauce -- at least for now.

So, what has been so successful for the fund?

Commodity picks like fertilizer plays Potash (NYSE: POT) and Mosaic (NYSE: MOS) have been big positions and have been big winners. Steel plays like US Steel (NYSE: X) have performed very nicely for CGM as well.

Looking at what worked is somewhat like looking into a rear-view mirror. These gains were in the past. What's Heebner and team buying now?

While the markets were up at the end of the trading day, there would be no other way to describe the day besides boring. The good news is that boring days are needed after periods of major volatility.

Today's news could have easily been dominated by a rise in weekly jobless claims hitting a high not seen since September 2005, with a reading of 407,000. The market was only looking for 365,000 to 375,000. But taking the center stage were Ben Bernanke, Jamie Dimon, and Alan Schwartz all defending the bailout and buyout Bear Stearns Companies (NYSE: BSC) in front of Congressional hearings for a second day. Below are the unofficial closing prices for today's US exchange levels

• DJIA 12,626.03 (+20.20; +0.16%)
• S&P500 1,369.30 (+1.77; +0.13%)
• NASDAQ 2,363.30 (+1.90; +0.08%)
• 10YR-TBond 3.591% (+0.008)
• 52-week lows

On last night's MAD MONEY on CNBC, Jim Cramer made a review of "alternative energy stocks" he recommended earlier this year since his coverage of the green-tech picks back in April based upon a Massachusetts court ruling that was going to be a homerun for the sector. He gave a pretty large list that was in reality just a review of many stocks that benefit either directly or indirectly from "greener" movements. Here is the "full list" of his eight stocks he reviewed tonight, and there are several more from call-ins.

His Top Pick in the group is MEMC Electronic Materials, Inc. (NYSE: WFR) as it has an arms merchant business model for the solar market. It makes wafers for solar panels and is too good to pass up. He said it's cheap and he thinks out of all green stocks that this one is still bargain.

You might want to know that MEMC already has a $16 billion market cap, but the forward growth rates in this part of its business are hard to argue against. This movement in "green" strategy has just recently helped the stock get back above levels seen in the late 1990's. Keep in mind that this one also produces wafers for the global semiconductor industry, so it isn't a pure-play in the sector. This one closed up big with the sector today at $74.74, but shares traded up 3% in after-hours after-hours trading to what will be a new high.

A couple of 24/7 Wall St. comments in the alternative energy area:

• An even more interesting analyst call in alternative energy today was where Lazard Capital called Capstone Turbine Corporation (NASDAQ: CPST) as a potential double to $2.50 per share. This one has been around forever and used to be considerably higher.
  
• If you want a more diversified play, you can always look at the best ETF in the sector: PowerShares WilderHill Clean Energy (AMEX: PBW).

Jon Ogg produces the Special Situation Investing Newsletter; he does not own individual stocks he covers.

John McNay, portfolio manager of Essex Investment Management, provided some good investment ideas on the evolving high-tech power business in this weekend's Barron's Magazine (subscription required). A few of these we blogged about in the past, but they're worth noting again.

• Sunpower Corporation (NASDAQ: SPWR), the Cypress Semiconductor Corporation (NYSE: CY) spin off, makes semiconductors for solar cells and solar panels
• MEMC Electronic Materials Inc (NYSE: WFR) makes the polysilicon that is needed to manufacture the solar cells and panels based on semiconductor technology
• Suntech Power Holdings (NYSE: STP), First Solar Inc (NASDAQ: FSLR), Canadian Solar Inc (NASDAQ: CSIQ) and Trina Solar (NYSE: TSL) were other stocks mentioned.

Sunpower and MEMC we have blogged about and know the companies reasonably well. The others you have to do your homework on, as these are new ideas to this Fly.

TJ Rodgers, Cypress Semiconductor's CEO, referred to Sunpower as Intel during the 1970s. That is a big statement. This is an important industry that will get a lot of investors' attention during the next five years. Solar energy utilizing semiconductor technology is an investment theme that is still in its very early stages.

SunPower Corporation (NASDAQ: SPWR), the Cypress Semiconductor founded company, has performed well since going public. The stock has moved up to $43, increasing from the mid-20s when it initially started trading.

SunPower makes solar electric power products based on semiconductor technology. Due to the strong growth of these semiconductors, management has cited that getting access to the much needed materials might limit SunPower's growth.

In this weekend's Barron's interview (subscription required), Michael Cahill, portfolio manager of Chilton Investment, has found a way for investors to possibly profit from any supply shortages that SunPower might face.

Cahill recommends the purchase of MEMC Electronic Materials (NYSE: WFR). For SunPower to make its chips, it needs a lot of polysilicon, the material used to manufacture semiconductor wafers. However, as this new solar application for semiconductors takes off, polysilicon will most likely be in short supply.

MEMC Electronic earned $2.07 for 2006 and Cahill expects earnings to hit $3.00 in 2007 and $4 per share by 2008. MEMC Electronic appears to be a way to profit from the take off of the solar semiconductor business.