MOST NOTEWORTHY: O'Reilly Automotive, Corning and Lincoln National were today's noteworthy downgrades:

• William Blair downgraded O'Reilly Automotive (NASDAQ: ORLY) to Market Perform from Outperform following weak Q1 results, citing the potential for further downward EPS revisions.
  
• Thomas Weisel downgraded Corning Inc. (NYSE: GLW) to Market Weight from Overweight citing balanced risk/reward given the backdrop of a maturing LCD penetration and generational upgrade cycle, and the challenging environment.
  
• Wachovia downgraded Lincoln National Corp. (NYSE: LNC) to Market Perform from Outperform as they believe the weak Q1 market weakness will impact profitability.

OTHER DOWNGRADES:

• Smith International (NYSE: SII) was cut to Perform from Outperform at Oppenheimer.
  
• Delphi Financial (NYSE: DFG) was downgraded at Friedman Billings to Market Perform from Outperform.
  
• CIBC downgraded Biovail (NYSE: BVF) to Sector Performer from Sector Outperformer.

MOST NOTEWORTHY: Total SA, HLTH Corp, Aflac First Solar and Town Sports were today's noteworthy upgrades:

• Citigroup upgraded Total SA (NYSE: TOT) to Buy from Hold following the company's Q3 results. JP Morgan upgraded shares to Overweight from Neutral, as they believe the company's Q3 results underlined the strength of exploration and production growth prospects versus peers.
  
• Friedman Billings raised its rating on HLTH Corporation (NASDAQ: HLTH) to Outperform from Market Perform following the company's proposal to merge into WebMD Health Corp (NASDAQ: WBMD) for a combination of cash and stock.
  
• The firm also added shares of Aflac (NYSE: AFL) to its Top Picks List, as they believe Aflac is the only high quality, defensive growth story in the Life Insurance sector.
  
• CIBC upgraded shares of First Solar (NASDAQ: FSLR) to Sector Outperformer from Sector Performer following the Q3 upside and set a $230 target on the stock.
  
• Banc of America upgraded shares of Town Sports (NASDAQ: CLUB) to Neutral from Sell on valuation as they believe the downside risk is now priced into the stock.

OTHER UPGRADES:

• Credit Suisse upgraded Nortel Networks (NYSE: NT) to Neutral from Underperform.
  
• Merrill upgraded Lincoln National (NYSE: LNC) to Buy from Neutral.
  
• Tyson Foods (NYSE: TSN) was raised to Market Perform from Underperform at Wachovia.