NEW YORK (Standard&Poor's) Dec. 18, 2006--Standard&Poor's Ratings Services said today its long-term ratings on Woonsocket, R.I.-based CVS Corp., including the 'BBB+' corporate credit ratings, remain on CreditWatch with positive implications. The ratings were initially placed on CreditWatch Nov. 2, 2006, when CVS announced a definitive agreement to merge with Caremark Rx Inc. (BBB/Stable/--). The 'A-2' short-term rating on CVS is not on CreditWatch. This CreditWatch update follows Express Scripts Inc.'s (BBB/Watch Negative/--) unsolicited offer of $26 billion to acquire Caremark Rx. The Express Scripts' bid is a 15% premium over the CVS offer. "While the potential merger of CVS and Caremark would be a positive for CVS, it could be less positive if CVS changes the