MOST NOTEWORTHY: MedImmune, Inc (MEDI), Take-Two Interactive Software (TTWO) and Tractor Supply Co (TSCO) were some of today's more notable downgrades:
- Bear Stearns downgraded MedImmune Inc (NASDAQ: MEDI) to Peer Perform from Outperform based on limited upside over the next 6-12 months.
- Take-Two Interactive Software (Nasdaq: TTWO) was cut by Kaufman to Sell from Hold with a $17 target. Kaufman believes Take-Two is overvalued based on fundamentals.
- Tractor Supply (NASDAQ: TSCO) was downgraded by Matrix to Sell from Hold. The firm expects high livestock feed and fertilizer prices to cut demand for Tractor Supply's target customer base.
OTHER DOWNGRADES:
- Martin Midstream Partners LP (NASDAQ: MMLP) was downgraded to Sector Perform from Outperform based on valuation.
- Friedman Billings cut Opteum Inc (NYSE: OPX) to Underperform from Market Perform citing the mounting losses in sub-prime mortgage loans and notes that servicing rights are also under pressure.
- JP Morgan downgraded OMI Corp (NYSE: OMM) to Neutral from Overweight.
- Kaufman downgraded First Charter Corp (NASDAQ: FCTR) to Market Perform from Outperform, citing the macro environment for the downgrade.
- CIBC downgraded Saifun Semiconductors Ltd (NASDAQ: SFUN) to Sector Performer from Outperform after checks in Asia indicated that Hynix is no longer considering NROM as they believe SFUN's licensing momentum is diminishing.
Analyst summaries provided by TheFlyOnTheWall.com (subscription required).
MOST NOTEWORTHY: Today's noteworthy upgrades include ConAgra Foods, Inc (CAG), Dell Inc (DELL), Ryland Group, Inc (RYL) and Volterra Semiconductor Corp (VLTR). 
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