Analyst upgrades, downgrades and initiations: GOOG, HOG, NOK, SWY, WAG, WSM ...

Analyst upgrades:

Keefe Bruyette upgraded Intercontinental Exchange (NYSE: ICE) to Outperform from Market Perform on expectations that derivatives trading will increase in the coming quarters.
NutriSystem (NASDAQ: NTRI) was upgraded to Buy from Neutral by Janney Montgomery, which believes that the company's earnings have hit bottom, while the company could report better-than-expected Q1 results.
Harley-Davidson (NYSE: HOG) was upgraded to Outperform from Sector Perform at RBC Capital. The firm thinks the company is an early-cycle story that has significant upside potential.
UBS upgraded Walgreen (NYSE: WAG) to Buy from Neutral citing cost cutting efforts and slowing store growth.
Google (NASDAQ: GOOG) was upgraded to Buy from Hold at Benchmark Co.
Safeway (NYSE: SWY) was upgraded to Buy from Hold by BB&T.
Needham upgraded Targacept (NASDAQ: TRGT) to Buy from Hold.
Sierra Wireless (NASDAQ: SWIR) was raised to Buy from Hold at Jesup & Lamont.

Analyst downgrades:

Goldman Sachs dropped Williams-Sonoma (NYSE: WSM) to Neutral from Buy based on valuation.
JPMorgan downgraded Allegheny Technologies (NYSE: ATI) on valuation and concerns Q4 guidance could disappoint investors.
F5 Networks (NASDAQ: FFIV) was downgraded to Perform from Outperform by Oppenheimer based on valuation.
Shaw Group (NYSE: SHAW) was downgraded to Neutral from Outperform at RW Baird.
Scientific Games (NASDAQ: SGMS) was downgraded to Neutral from Overweight at JPMorgan.
Citigroup dropped Liberty Capital (NASDAQ: LCAPA) to Hold from Buy.
RBS downgraded Nokia (NYSE: NOK) to Hold from Buy.

Analyst initiations:

Benchmark Co. initiated Aspen Technology (OTC: AZPN) with a Hold rating. The firm expects Aspen's shares to be range-bound pending clarity on the company's accounting restatement, business model transition, and likely shelf registration.
Barclays initiated Medtronic (NYSE: MDT) with an Overweight rating and $48 target. Credit Suisse started SAIC (NYSE: SAI) with an Outperform rating and $22 target.
Aeropostale (NYSE: ARO) was initiated with a Buy rating and $51 target at Auriga.
Aetna (NYSE: AET) was reinstated with an Underperform rating at BofA/Merrill.
Plains Exploration (NYSE: PXP) was initiated with an Outperform at FBR Capital.
Humana (NYSE: HUM) was reinstated with a Buy at BofA/Merrill.