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.