NEW YORK (TheStreet) -- CHANGE IN RATINGSAircastle ( AYR) upgraded to Buy at TheStreet Ratings. Ameren ( AEE) upgraded at Morgan Stanley to Overweight, Morgan Stanley said. $37.50 price target. Exiting the merchant generation business will help earnings. Big Lots ( BIG) rated new Buy at Citigroup. $36 price target. Canada turnaround tacking above plan. Camden National ( CAC) upgraded to Buy at TheStreet Ratings. Discover ( DFS) downgraded at FBR from Outperform to Market Perform, FBR Capital Markets said. $42 price target. Company is facing rising operating costs. Brinker ( EAT) upgraded at Sterne Agee from Neutral to Buy, Sterne Agee said. $36 price target. Channel checks suggest better sales visibility. F5 Networks ( FFIV) rated new Outperform at FBR. $120 price target. Fears of competition have been overblown for the time being. Harman ( HAR) rated new Neutral at Guggenheim. $46 price target. Company will likely continue to experience volatility in Europe. IBM ( IBM) rated new Buy at Topeka. $245 price target. Company is leveraged to emerging market trends. Nike ( NKE) downgraded at Janney from Buy to Neutral, Janney Montgomery said. Valuation call, based on a fair value of $110. Verifone ( PAY) rated new Sector Perform at Pacific Crest. Company will struggle to receive a higher earnings multiple. Research in Motion ( RIMM) downgraded at Paradigm to Hold, Paradigm Capital said. $14.50 price target. Company is likely to see lower services revenue.