Analyst upgrades:

• Cowen upgraded Aaron Rents (NYSE: RNT) to Outperform from Neutral and believes the company's business model is gaining momentum despite the difficult environment. The firm views valuation as attractive.
  
• Citigroup upgraded shares of MedCath (NASDAQ: MDTH) to Hold from Sell on valuation following the recent sell-off. The company's target was lowered to $9 from $19.
  
• Stanford upgraded AeroVironment (NASDAQ: AVAV) to Buy from Hold based on valuation and because they believe its visibility over the next year has improved.
• Chiquita Brands (NYSE: CQB) was lifted to Buy from Hold at BB&T.
  
• Chico's FAS (NYSE: CHS) was upgraded to Neutral from Sell at UBS.
  
• FCStone (NASDAQ: FCSX) was raised to Strong Buy from Outperform at Raymond James.

Analyst downgrades:

• RBC Capital downgraded Clearwire (NASDAQ: CLWR) to Sector Perform from Outperform based on reduced valuation parameters and lack of catalysts. The company's target was lowered to $9 from $15.
• Kellogg (NYSE: K) and Coca-Cola (NYSE: KO) were cut to Neutral from Buy at UBS.
  
• Evergreen Solar (NASDAQ: ESLR) was downgraded at JP Morgan to Underweight from Neutral.
• Deutsche Telekom (NYSE: DT) was downgraded to Neutral from Buy at Goldman and to Hold from Buy at Deutsche Bank.

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

• CarMax Inc. (NYSE: KMX) Q1 profits tumbled despite its aggressive expansion program.
• Chiquita Brands International Inc. (NYSE: CQB) warned it would miss earnings due to cost hikes.
• Circuit City Stores Inc. (NYSE: CC) Q1 loss widened as same-store sales dwindled.
• Commercial Metals Co. (NYSE: CMC) Q3 profits declined despite strong demand, but beat estimates.
• Coventry Healthcare Inc. (NYSE: CVH) lowered its Q2 and full-year outlooks after a disappointing April.
• FedEx Corp. (NYSE: FDX) missed estimates on higher fuel prices and offered lackluster guidance.
• Ford Motor Co. (NYSE: F) warned that 2008 full-year results would be worse than those of 2007.
• General Electric Co. (NYSE: GE) was downgraded by JP Morgan because of risk to earnings.
• J.M. Smucker Co. (NYSE: SJM) missed Q4 earnings expectations despite acquisitions-based growth.
• La-Z-Boy Inc. (NYSE: LZB) said it swung to a Q4 loss due to diminishing retail sales.
• Lehman Brothers Holdings Inc. (NYSE: LEH) CEO expressed his disappointment in the Q2 results.
• Merrill Lynch & Co. (NYSE: MER) profit warnings and write-downs hit the rumor mill.
• Morgan Stanley (NYSE: MS) beat low expectations despite a hefty decline in Q2 profits (see transcript).
• Pier 1 Imports Inc. (NYSE: PIR) narrowed its Q1 loss but still fell short of expectations.
• Winnebago Industries Inc. (NYSE: WGO) posted dismal Q3 results but still beat low expectations.

More earnings highlights from this week: Goldman Sachs, Best Buy, General Mills, Carnival and others

MOST NOTEWORTHY: UBS AG, Coventry Health, Express Scripts and Medco Health were today's noteworthy downgrades:

• Credit Suisse downgraded shares of UBS (NYSE:UBS) to Neutral from Outperform as they believe UBS will have difficulty rebuilding the franchise and do not expect a quick recovery for its private bank unit.
  
• Wachovia downgraded Coventry Health (NYSE:CVH) to Market Perform from Outperform citing concerns regarding visibility around higher than expected inpatient/outpatient costs following reduced 2008 guidance.
  
• UBS downgraded Express Scripts (NASDAQ:ESRX) and Medco Health to Neutral from Buy citing the Pfizer (NYSE:PFE)/Ranbaxy settlement, which reduces the likelihood of a generic Lipitor launch in 2010.

OTHER DOWNGRADES:

• Goldman downgraded ENI SpA (NYSE:E) to Neutral from Buy and removed the stock from the Pan-Europe Conviction Buy List.
  
• Huntsman (NYSE:HUN) was downgraded to Underperform from hold at Jefferies.
  
• Commercial Metals (NYSE:CMC) was cut at Citigroup to Hold from Buy.

MOST NOTEWORTHY: Capstone Turbine, Insulet and Teradata were today's noteworthy initiations:

• Merriman believes Capstone Turbine (NASDAQ: CPST) is well-positioned for rapid growth as capacity constraints and dependence on subsidies drive the adoption of clean, dependable hydrocarbon-based technologies. Shares were assumed with a Buy rating.
  
• JMP Securities initiated Insulet (NASDAQ: PODD) with an Outperform rating and $29 target and expects increased adoption of the company's OmniPod disposable, tubeless insulin pump.
  
• Pacific Crest initiated Teradata (NYSE: TDC) with an Underperform rating. The firm is a seller of shares given the slowing economy and the company's exposure to larger IT deals.

OTHER INITIATIONS:

• Commercial Metals (NYSE: CMC) was initiated at UBS with an Outperform rating and $37 target.

MOST NOTEWORTHY: Polaris Industries, Edwards Lifesciences, BearingPoint and Fortis were today's noteworthy upgrades:

• Rochdale upgraded Polaris Industries (NYSE: PII) to Buy from Hold, as they have increased confidence in the company's ability to achieve estimates.
  
• Piper upgraded shares of Edwards Lifesciences (NYSE: EW) as they believe the bad news is behind the company with a U.S. turnaround expected in 2008.
  
• Jefferies raised shares of BearingPoint (NYSE: BE) to Hold from Underperform on valuation as they believe the risk/reward is neutral following the recent pullback.
  
• Fortis (OTC: FORSY) was upgraded to Outperform from Peer Perform at Bear Stearns. The firm upgraded shares on valuation as they believe the recent weakness is overdone.

OTHER UPGRADES:

• Goldman Sachs added Research in Motion Limited (NASDAQ: RIMM) and Commercial Metals (NYSE: CMC) to its Conviction Buy List.
• Credit Suisse upgraded Varian Semiconductor (NASDAQ: VSEA) to Outperform from Neutral.
  
• Bear upgraded Bruker Biosciences (NASDAQ: BRKR) and Hutchison Telecom (NYSE: HTX) to Outperform from Peer Perform.
  
• Banc of America upgraded Werner Enterprises (NASDAQ: WERN) and J.B. Hunt (NASDAQ: JBHT) to Neutral from Sell.

MOST NOTEWORTHY: Commercial Metals (CMC), KKR Financial (KFN), Career Education (CECO), Ann Taylor (ANN) and Intel (INTC) were today's noteworthy upgrades:

• CIBC upgraded Commercial Metals (NYSE: CMC) to Sector Outperformer from Sector Performer based on valuation.

• KKR Financial (NYSE: KFN) was raised to Outperform from Market Perform at Friedman Billings, following managements detailed conference call and managements prudent and rapid actions to address the sale of its Rambus (RMBS) portfolio.

• Bear Stearns upgraded Career Education (NASDAQ: CECO) to Outperform from Peer Perform based on valuation.

• Ann Taylor (NYSE: ANN) was upgraded to Outperform from Market Perform at Piper Jaffray due to the upside at the company's LOFT division and the firm's belief that there is upside to their 2008/2009 estimates for Ann Taylor.

• Credit Suisse upgraded shares of Intel (NASDAQ: INTC) to Outperform from Underperform based on expected margin expansion, a more benign competitive environment in the MPU sector, better positioning vs. AMD (AMD) at the high-end, and strong demand trends...

OTHER UPGRADES:

• Citigroup upgraded Sovereign Bancorp (NYSE: SOV) to Buy from Hold.

• Network Appliances (NASDAQ: NTAP) was upgraded to Buy from Neutral at Merrill Lynch and Caris raised shares to Buy from Above Average.

• JP Morgan added Continental (NYSE: CAL) to its Focus List. Punk upgraded Washington Mutual (WM) to Buy from Market Perform.

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