Bullish calls for Micron and Walmart but not the best news for Dollar General. Chipmaker Micron Technology (MU) is getting a lot of endorsements today. Needham upgraded the stock to a 'Strong Buy' from 'Buy' with a $50 price target. The firm says Micron is "making the right decisions to invest in controller and firmware businesses." JMP Securities also increased its price target for the stock to $36. The firm has an Outperform rating on the shares. And Jefferies raised its price target for Micron to $38 with a 'buy rating.' Morgan Stanley initiates coverage for Walmart (WMT) with a positive note. But not the best news for Dollar General (DG) as Goldman Sachs removes the discount retailer from its 'conviction list'. TheStreet's Susannah Lee reports from Wall Street.