Analyst calls: NZ, CEG, WSM, CBT, ELN ...

Analyst upgrades:

Merriman upgraded shares of Netezza (NYSE: NZ) to Buy from Neutral following the company's solid Q2 results as they believe it is well-positioned for strong operating results heading into 2H09.
JP Morgan raised Cabot (NYS: CBT) to Overweight from Neutral. The firm expects 2009 to be a better year given lower raw material costs and higher contract prices.
JP Morgan also upgraded Royal Ahold (OTC: AHONY) to Overweight from Neutral on valuation.
Liberty International (OTC: LBYIY) was upgraded to Hold from Sell at Deutsche Bank.
BMO Capital upgraded Royal Bank (NYSE: RY) to Market Perform from Underperform and Bank of Montreal (NYSE: BMO) to Outperform from Market Perform.

Analyst downgrades:

Jefferies downgraded shares of Constellation Energy (NYSE: CEG) to Underperform on Hold on concerns the company will come under increasing pressure to issue equity. The firm lowered its target to $60 from $71.
Thomas Weisel downgraded Williams-Sonoma (NYSE: WSM) to Market Weight from Overweight citing continued macro pressures.
Wachovia has concerns that Kayne Anderson's (NYSE: KED) book value will be pressured by its investment in ProPetro Services, trading losses associated with SemGroup, and negative developments at Quest Midstream. The firm cut shares of Kayne to Market Perform from Outperform.
Energy Conversion (NASDAQ: ENER) was downgraded to Neutral from Buy at Piper.
Deutsche Bank cut International Paper (NYSE: IP) and Domtar (NYSE: UFS) to Hold from Buy.
H&E Equipment (NASDAQ: HEES) was lowered at Credit Suisse to Neutral from Outperform.

Analyst initiations:

Morgan Stanley yesterday initiated Elan Corp (NYSE: ELN) with an Overweight rating. The firm sees a low-probability of a Tysabri withdrawal.
ThinkPanmure views On Semiconductor (NASDAQ: ONNN) as a nice turnaround story with opportunities for shares gains in notebooks and consumer gaming platforms. Shares were initiated with a Buy rating and $14 target.
Petrohawk Energy (NYSE: HK) was assumed with an Outperform rating at Morgan Keegan.
Regency Energy (NASDAQ: RGNC) was initiated at Merrill Lynch with a Neutral rating.