Every day, Wall Street analysts upgrade some stocks, downgrade others, and "initiate coverage" on a few more. But do these analysts even know what they're talking about? Today, we're taking one high-profile Wall Street pick and putting it under the microscope...Micron Technology (NASDAQ: MU) shares are on a tear.The stock price of this computer memory manufacturer -- maker of both DRAM and NAND flash memory for computers and mobile devices -- has raced ahead 86% in 52 weeks, leaving the S&P 500 in its dust.