Analyst upgrades:

• JP Morgan upgraded Astoria Financial (NYSE: AF) to Neutral from Underweight on valuation as it finds the stock fairly valued at current levels.
• Seagate Technology (NASDAQ: STX) was upgraded to Neutral from Sell at American Technology.

Analyst downgrades:

• Soleil downgraded Sunoco (NYSE: SUN) to Hold from Buy on valuation following the recent rally and is concerned about rising distillate inventories on the East Coast.
• Deutsche Bank downgraded MedCath (NASDAQ: MDTH) to Hold from Buy and lowered its target to $12.50 from $14 as it believes FY09 consensus estimates remain too high.
• Piper Jaffray downgraded ReneSola (NYSE: SOL) to Neutral from Buy and Canadian Solar (NASDAQ: CSIQ) to Sell from Neutral.
• LHC Group (NASDAQ: LHCG) was cut to Hold from Buy at Deutsche Bank.

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.

MOST NOTEWORTHY: DiamondRock Hospitality, Pzena Investment and Vodafone were today's noteworthy upgrades:

• DiamondRock Hospitality (NYSE: DRH) was upgraded to Outperform from Neutral at Baird, citing the newly-announced 4.8M repurchase plan, strong balance sheet and valuation.
  
• Keefe Bruyette upgraded shares of Pzena Investment (NYSE: PZN) to Market Perform from Underperform after the company announced February ending AUM.
  
• Goldman added Vodafone (NYSE: VOD) to its Conviction Buy List following the recent weakness as they expect the company to benefit from growth in wireless data.

OTHER UPGRADES:

• UBS raised Weyerhaeuser (NYSE: WY) to Buy from Neutral.
  
• Credit Suisse upgraded MedCath (NASDAQ: MDTH) and Lululemon (NASDAQ: LULU) to Outperform from Neutral.
  
• Goldman added Cardinal Health (NYSE: CAH) to its Conviction Buy List.

MOST NOTEWORTHY: Time Warner, MedCath and Schlumberger were today's noteworthy upgrades:

• UBS upgraded shares of Time Warner (NYSE: TWX) to Buy from Neutral on valuation and believes the company's focus on structural improvements and cost reductions will provide positive catalysts.
  
• MedCath (NASDAQ: MDTH) was upgraded to Outperform from Market Perform at Wachovia, as they view weakness following the Q1 miss due to a higher-than-expected option expense as a buying opportunity.
  
• Bear Stearns raised Schlumberger (NYSE: SLB) to Outperform from Peer Perform, as they believe the company is well-positioned for the next oilfield service business cycle and valuation.

OTHER UPGRADES:

• SunTrust upgraded Carrizo Oil & Gas (NASDAQ: CRZO) to Buy from Neutral.
  
• Credit Suisse upgraded Eldorado Gold (NYSE: EGO) to Outperform from Neutral.
  
• Liberty Media (NASDAQ: LCAPA) was raised to Overweight from Equal Weight at Lehman.

MOST NOTEWORTHY: GlaxoSmithKline plc (GSK), RF Micro Devices, Inc (RFMD), BMC Software, Inc (BMC) and Tween Brands Inc (TWB) were today's noteworthy upgrades:

• GlaxoSmithKline (NYSE: GSK) was upgraded to Hold from Sell at Societe General on valuation.

• Jefferies upgraded shares of RF Micro Devices (NASDAQ: RFMD) to Buy from Hold and raised the target to $9.00 from $7.00 after their channel checks indicated RFMD's business has improved since its last earnings call.

• Cowen raised BMC Software (NYSE: BMC) to Neutral from Underperform citing valuation and improvements in the cash flow for their upgrade.

• Susquehanna upgraded Tween Brands (NYSE: TWB) to Positive from Neutral based on Justice's performance and recent buyback activity...

OTHER UPGRADES:

• Lenovo Group Ltd (OTC: LNVGY) was upgraded at Credit Suisse to Neutral from Underperform; JP Morgan upgraded Lenovo to Overweight from Neutral.

• Morgan Keegan upgraded Symmetricom, Inc (NASDAQ: SYMM) to Outperform from Market Perform.

• Goldman upgraded CDI Corp (NYSE: CDI) to Buy from Neutral.

• Stifel raised MedCath Corp (NASDAQ: MDTH) to Buy from Hold.

• Soleil upgraded VA Software Corp (NASDAQ: LNUX) to Hold from Sell.

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

MOST NOTEWORTHY: Aeropostale (ARO) and Halliburton (HAL) top today's initiations.

• Caris initiated Aeropostale, Inc. (NYSE:ARO) with an Above Average rating and said Aeropostale's strong inventory, management and same-store sales growth should bring significant upside to margins.
• Credit Suisse started Halliburton Company (NYSE:HAL) with a Neutral and $43 target.

OTHER INITIATIONS:

• Medcath Corp (NASDAQ:MDTH) was initiated by Citigroup with a Buy and $35 target, citing a solid portfolio, strong core operating results and valuation.
• Credit Suisse initiated J Crew Group, Inc. (NYSE:JCG) with an Outperform rating and $42 target. The firm said J Crew was an attractive turnaround story with opportunity for margin expansion.

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