Steve Tyler, Ryan Seacrest, Jennifer Lopez, Randy Jackson Steve Tyler, Ryan Seacrest, Jennifer Lopez, Randy Jackson

For the past eight years, American Idol has been appointment television for millions on Tuesday and Wednesday nights. Get ready to change that appointment, because Fox is taking the bold step of sliding its spectacularly successful reality franchise to Wednesday (performance show) and Thursday (results show).

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The reason: It's a move designed to flex some powerful programming muscle. The network has confidence that its other big Tuesday night hit, Glee, will continue to be strong. In shifting Idol, the strategy is designed to smash the competition on Thursdays, a night that television programmers dream of winning because it can attract major advertising dollars.    

"We've been trying to break that Thursday barrier for probably 20 years," says Fox alternative programming chief Mike Darnell. "The only way anyone's ever broken that barrier is with a big television show, like CSI, Grey's Anatomy, and Survivor. You have to make a big move, and we've got the biggest show on television, so that's a big move. 

The decision became clear, says Fox entertainment chief Kevin Reilly, once CBS moved Survivor from Thursdays to Wednesdays this season. That gave Fox the chance to establish a new stronghold on Thursdays, "because there's no reality competition."

"We were completely locked out of that night for many years," says Reilly. "Last year we made some inroads with Fringe, but now we've decided to really go for it. We've got a very high-class problem with Idol, which is the biggest appointment show of all. It comes on like a storm of its own when it's launched in January. So we looked at this and said, 'Now there's an opportunity on Thursday.'"

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