American Idol regained some of its viewers Thursday night after last week's additional slippage and even managed to edge out CBS in the 9:00 p.m. hour among viewers 18-49. CBS, however, continued to lead -- albeit just barely -- among total viewers averaging 13.52 million in primetime to Fox's 13.50 million -- for all intents and purposes a tie. Once again, the highest-rated show of the night was CBS's The Big Bang Theory with 17.3 million viewers. It was followed by Two and a Half Men with 13.4 million viewers. NBC's shows continued inhabiting the cellar. On a night that it once dominated, its highest-rated show was Law & Order: SVU, which drew just 3.9 millionviewers. Its lowest rated show was 1600 Penn with just 2.3 million, a show that probably would have been canceled by now if it existed on any other channel.