Shares of Medco Health (NYSE:MHS) and Express Scripts (NASDAQ:ESRX) could be poised to rebound after yesterday's report that the FTC may reject the merger deal between the two companies. While sources tell the NY Post the deal still has a better than 50% chance of FTC approval, a merger of commercial real estate data providers CoStar Group (NASDAQ:CSGP) and LoopNet (NASDAQ:LOOP-OLD) may be in danger.