Analyst upgrades 5-31-07: Yahoo! upgraded to Overweight

MOST NOTEWORTHY: Yahoo! (YHOO), Genzyme (GENZ) and Dress Barn (DBRN) were today's noteworthy upgrades:

Yahoo! Inc. (NASDAQ: YHOO) was upgraded to Overweight from Neutral at JP Morgan as the firm believes the company has addressed weakness in display advertising with recent partnership announcements and the acquisition of Right Media. Additionally, the firm still sees upside to Panama.
Genzyme Corp. (NASDAQ: GENZ) was upgraded to Buy from Neutral at Goldman Sachs, citing valuation and a favorable risk/reward.
Merriman upgraded shares of Dress Barn (NASDAQ: DBRN) to Buy from Neutral to reflect the improved sales trends in May and sees the stock trading at the high end of its peer group average or in a range of $25.50-$27.00.

OTHER UPGRADES:

Deutsche Telekom (NYSE: DT) was upgraded to Buy from Sell at Societe Generale, which also added shares to its Premium List.
Lehman Brothers upgraded AvalonBay Communities (NYSE: AVB) to Equal Weight from Underweight, as the firm views AVB as a close comp to Archstone-Smith Trust (NYSE: ASN). Lehman also upgraded Post Properties (NYSE: PPS) to Equal Weight from Underweight, citing industry M&A activity, and China Life Insurance (NYSE: LFC) to Buy from Neutral, citing valuation.
Deutsche Bank upgraded shares of BG Group plc (NYSE: BRG) to Buy from Hold to reflect expected growth in the company's liquefied natural gas business.
Red Hat Inc. (NYSE: RHT) was upgraded to Outperform from Neutral at Robert W Baird, which expects improved performance at JBoss and a positive mix shift in the core O/S business following the release of RHEL 5.