MOST NOTEWORTHY: Patterson Companies, Virgin Media and MannKind were today's noteworthy downgrades:

• Patterson (NASDAQ:PDCO) was downgraded to Neutral from Outperform at Baird, as the firm's checks indicate industry fundamentals have softened and it sees greater near-term risk for dental consumables than dental equipment.
  
• Virgin Media (NASDAQ:VMED) was cut to Hold from Buy at Jefferies as they believe the company's results could be under pressure given the continued competitive activity and potential weakening of the UK economy.
  
• Piper downgraded shares of MannKind (NASDAQ:MNKD) to Neutral from Buy and lowered their target to $1.50 after Pfizer (NYSE:PFE) discontinued inhaled insulin Exubera due to an increase in lung cancer cases.

OTHER DOWNGRADES:

• Lehman cut Cheniere Energy (LNG) to Equal Weight from Overweight.
  
• Pantry (PTRY) was cut to Market Perform from Outperform at Friedman Billings.
  
• JP Morgan lowered Watsco (WSO) to Neutral from Overweight.

MOST NOTEWORTHY: Cott Corp, Hartford Financial, Allstate and Valero Energy were today's noteworthy upgrades:

• Lehman upgraded Cott Corp (NYSE: COT) to Equal Weight from Underweight citing recent management changes, a focus on CSD business, and new product discipline.
  
• Bernstein believes the entire non-life insurance group is oversold and that it is time to buy; the firm upgraded Hartford Financial (NYSE: HIG) and Allstate (NYSE: ALL) to Outperform from Market Perform.
  
• Valero Energy (NYSE: VLO) was raised to Buy from Hold at Deutsche Bank on valuation with the stock trading at a -30% discount to NAV while the asset market for U.S. refineries is strong.

OTHER UPGRADES:

• Goldman added Cisco (NASDAQ: CSCO) to its Conviction Buy List.
  
• RBC Capital upgraded BJ Services (NYSE: BJS), Halliburton (NYSE: HAL) and Patterson-UTI Energy (NASDAQ: PTEN) to Outperform from Sector Perform.
  
• Friedman Billings upgraded the Semiconductor Capital Equipment sector to Overweight from Market Weight.

Just because a company is in the health are field, it doesn't mean it's a buy. That's because investors have figured out that future demand for a product does not translate into unexpectedly high profit for the companies that meet the demand.

Obviously demand for medical products and services is going to rise as 77 million baby boomers age. But that demand does not necessarily translate into making money -- either in the product or stock markets. Why not? Because the competition is fierce. Not only are rivals going after each other with aggressive marketing but in many cases the government or pharmacy benefit managers are the buyers. And these buyers cap prices -- often at levels that make it difficult for suppliers to make a decent profit.

Furthermore, companies in this industry must invest considerable amounts in R&D to develop new products since they can't rely on profits from products that lose patent protection due to competition from generics. And the success rates of those R&D efforts seem to be dropping -- leaving many competitors with high costs, declining revenues, and uncertain futures.

MOST NOTEWORTHY: Patterson-UTI Energy, Nabors Industries, US Steel Group, Cooper Companies and Continental AG were today's noteworthy upgrades:

• Bernstein upgraded Patterson-UTI Energy Inc (NASDAQ: PTEN) and Nabors Industries Limited (NYSE: NBR) to Outperform from Market Perform citing valuations and secular growth trends.
• Citigroup upgraded US Steel Corporation (NYSE: X) to Buy from Hold and raised their target to $118 to reflect operating catalysts and their expectations for domestic steel markets to improve in Q4 and 2008.
• Cooper Companies Inc (NYSE: COO) was also upgraded to Buy from Hold at Citigroup despite the lowered guidance as they believe the company's products are improving and earnings upside is possible.
• WestLB upgraded Continental AG (OTC: CTTAY) to Buy from Hold after the tire marker announced plans to reorganize its company structure into six divisions following the purchase of Siemens AG's (NYSE: SI) VDO automotive unit.

OTHER UPGRADES:

• Tempur Pedic International (NYSE: TPX) was upped to Sector Outperformer from Sector Performer at CIBC World Markets.
• Friedman Billings upgraded shares of Stone Energy Corporation (NYSE: SGY) to Outperform from Market Perform.
• Deutsche Bank upgraded shares of Occidental Petroleum Corporation (NYSE: OXY) to Buy from Hold.
• Fifth Third Bancorp (NASDAQ: FITB) was raised to Market Perform from Underperform at Bernstein.

MOST NOTEWORTHY: Warner Music Group Corp (WMG), Red Robin Gourmet Burgers, Inc (RRGB) and Berkshire Hathaway Inc (BRK.A) were some of today's notable upgrades:

• Pali Capital upgraded shares of Warner Music Group Corp (NYSE: WMG) on valuation.

• Matrix USA upgraded Red Robin Gourmet Burgers Inc (NASDAQ: RRGB) to Hold from Sell on valuation.

• Berkshire Hathaway Inc (NYSE: BRK.A) was upgraded to In Line from Underperform at Fox-Pitt, Kelton.

OTHER UPGRADES:

• UBS upgraded ARM Holdings plc (NASDAQ: ARMHY) to Buy from Neutral as the firm believes the company will be a significant beneficiary of the acceleration in 3G handset adoption in 2007.

• Wachovia upgraded Pactiv Corp (NYSE: PTV) to Outperform from Market Perform on valuation.

• Baird raised Patterson Companies (NASDAQ: PDCO) rating to Outperform from Neutral.

• BMO Capital raised UCBH Holdings, Inc (NASDAQ: UCBH) rating to Outperform from to Market Perform.

• O2Micro International Ltd (NASDAQ: OIIM) was upgraded to Buy from Neutral at Oppenheimer citing a possible near-term court settlement with Samsung, which provides significant earnings leverage.

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

MOST NOTEWORTHY: NYSE Group Inc (NYX), Patterson-UTI Energy (PTEN) and HomeBanc Corp (HMB) were today's more notable downgrades:

• JP Morgan downgraded shares of the NYSE Group Inc (NYSE: NYX) to Underweight from Neural to reflect their belief that the company's float will increase significantly in March due to the acquisition of Euronext and the lockup expiration. JP Morgan believes this could bring selling pressure.
  

• Credit Suisse downgraded shares of Patterson-UTI Energy (NASDAQ: PTEN) citing negative earnings impact from share losses and industry capacity additions.

• Shares of HomeBanc Corp (NYSE: HMB) were downgraded to Underperform from Market Perform with a $2.60 target at Friedman Billings based on continued losses and an unlikely sale given market conditions.

OTHER DOWNGRADES:

• Wachovia downgraded Hub International Ltd (NYSE: HBG) to Market Perform from Outperform following news of a private-equity acquisition for $40 a share.

• UBS downgraded Bed Bath & Beyond Inc (NASDAQ: BBBY) to Neutral from Buy on valuation.

• Citigroup downgraded Burlington Northern Santa Fe Corp (NYSE: BNI) to Hold from Buy.

• AG Edwards cut Teekay LNG Partners (NYSE: TGP) and Teekay Offshore Partners (NYSE: TOO) to Hold from Buy citing valuation.

• Raymond James downgraded shares of Marvel Entertainment Inc (NYSE: MVL) to Market Perform from Outperform.

• Lazard downgraded Thoratec Corp (NASDAQ: THOR) to Sell from Hold with a $15 target. They recommend selling shares ahead of a likely FDA decision to call an advisory panel for HeartMate II.

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