MOST NOTEWORTHY: MGM Mirage (MGM), USA Truck, Inc (USAK), Knightsbridge Tankers Ltd (VLCCF), Monolithic Power Systems, Inc (MPWR) and Stanley, Inc (SXE) topped out today's noteworthy upgrade list:

• Prudential upgraded shares of MGM Mirage (NYSE: MGM) to Overweight from Neutral on valuation, as the firm believes the recent weakness presents a buying opportunity.

• USA Truck Inc (NASDAQ: USAK) was raised to Equal Weight from Underweight at Stephens based on valuation.

• Jefferies upgraded shares of Knightsbridge Tankers Ltd (NASDAQ: VLCCF) to Hold from Underperform to reflect the company's five vessels now operating on long-term time charter contracts and its recent entry into the dry bulk shipping sector.

• Monolithic Power (NASDAQ: MPWR) was upgraded to Buy from Hold at Deutsche Bank following its patent win case against O2Micro International Ltd (OIIM).

• Wachovia upgraded Stanley Inc (NYSE: SXE) to Outperform from Market Perform based on its strong Q4 report and guidance...

OTHER UPGRADES:

• Cognos Inc (NASDAQ: COGN) was upgraded to Outperform from Sector Perform at Pacific Crest.

• Riverbed Technology, Inc (NASDAQ: RVBD) was raised to Overweight from Market Weight at Thomas Weisel.

• Stifel upgraded Priceline.com Inc (NASDAQ: PCLN) to Buy from Hold.

• Barrington raised X-Rite, Inc (NASDAQ: XRIT) To Outperform from Market Perform.

• Morgan Stanley raised Principal Financial Group Inc (NYSE: PFG) to Equal Weight from Underweight.

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

MOST NOTEWORTHY: Cisco Systems Inc (CSCO), Continental (CAL) and Caterpillar inc (CAT) complete the list of notable downgrades:

• Citing peak employee productivity and margin expansion difficulties, Citigroup downgraded Cisco Systems Inc (NASDAQ: CSCO) from its previous Buy rating and assumed the company with a Hold rating.

• Goldman Sachs downgraded Continental Airlines Inc (NYSE: CAL) to Sell from Neutral on valuation.

• JP Morgan assumed coverage of Caterpillar Inc (NYSE: CAT) with an Underweight rating, downgraded from its previous Neutral rating.

OTHER DOWNGRADES:

• Following CIBC's outlook for the Paper & Forest sector through 2008, the firm downgraded Bowater Inc (NYSE: BOW) to Sector Underperformer from Sector Performer. The broker believes pulp, paper and packaging prices are near cyclical highs.

• Goldman Sachs expects a slowdown in revenue growth and margins in 2007 for TRW Automotive Holdings Corp (NYSE: TRW) and added the company to its America's Conviction Sell List.

• USA Truck Inc (NASDAQ: USAK) was downgraded to Market Perform from Outperform at Morgan Keegan following the trucking company's disappointing Q4, guidance and lack of near-term catalysts.

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

MOST NOTEWORTHY: Apple Computer, Inc. (NASDAQ:AAPL), First Data (FDC) and ASM International (ASMI) top today's extensive downgrade list.

• Apple was downgraded to Hold from Buy at Citigroup, citing valuation and the unlikely introduction of the new video iPod before the holiday season.
• First Data was downgraded to Neutral from Overweight at J.P. Morgan based on valuation and expectations of a Q3 miss.
• CIBC downgraded ASM International to Sector Performer from Sector Outperform based on checks that indicated Intel (INTC) is pushing out adoption of ASMI's atomic layer disposition tool for high-k at 45mn. They note a delay would be positive for Applied Materials (AMAT).

OTHER DOWNGRADES:

• Due to the change in management and lowered guidance, both Credit Suisse and KeyBanc/McDonald downgraded IT service provider Keane (KEA).
• ThinkEquity downgraded CryptoLogic (CRYP) to Source of Funds from Accumulate based on the ratification of the Internet gambling bill that will impact earnings.
• Boston Beer (SAM) was downgraded to Neutral from Overweight on valuation.
• USA Truck (USAK) was downgraded by Stephens to Underweight from Equal Weight, citing a less certain 2007 trucking environment and the recent stock offering.

Ratings summary provided courtesy of TheFlyOnTheWall.com.