From Mediaweek:
Led by a two-hour installment of the now Hollywood-based American Idol, dominant Fox beat the four competing networks combined by 5.26 million viewers and 56 percent among adults 18-49. American Idol scored a typically massive 29.87 million viewers and a 12.2 rating/29 share among adults 18-49, building in each half-hour as follows:
American Idol
8:00 p.m. Viewers: 26.17 million, A18-49: 10.6/27
8:30 p.m. Viewers: 29.76 million, A18-49: 12.1/29
9:00 p.m. Viewers: 31.61 million, A18-49: 13.0/30
9:30 p.m. Viewers: 31.95 million, A18-49: 13.3/30