By James Hibberd
July 21, 2012 at 06:18 PM EDT

American Idol is once again becoming more compelling for its backstage drama

than its onscreen singing competitions. Sexobsessed sexagenarian Steven Tyler is out. Poised pro Jennifer Lopez says she’s gone too. The fate of snoozily affable Randy Jackson, who’s managed to survive years of high-profile shakeups on the Fox hit, is uncertain as well.

One thing is clear: American Idol will be reinvented again before the 12th season

launches in January. Though Tyler’s departure was announced last week, the decision to overhaul the show was effectively made months ago, when the 10th season suffered the biggest ratings drop in the series’ history. Idol was down 23 percent—to 18 million viewers— from the previous year. That’s still a large

enough audience to make Idol TV’s biggest non-sports program, but it’s an alarming

decline for a costly show that’s critical to Fox’s schedule. The drop prompted Chase Carey, COO of Fox parent company NewsCorp, to tell Wall Street last February that the show needs “fresh energy.”

Though the dealmaking is still in flux, the current frontrunner to deliver that new wattage is Mariah Carey — with Janet Jackson, Katy Perry,, Kanye West, and Fergie also on Fox’s wish list. Sources say Carey is deep into her talks with Fox and would probably score a paycheck on par with Lopez’s. (Negotiations started around $12 million a season, the same as Lopez’s first year, though will probably conclude closer to Lopez’s second-year rate of $15 million.) Despite reports that Randy Jackson will exit, insiders now expect him to stay, especially Carey comes on board (Jackson manages the pop singer).

As for Lopez, the singer claims she’s leaving, but Fox hasn’t yet announced her departure. Lopez gave a vague interview on July 16 that left some wiggle room (“I don’t know if it’s even done yet,” she told GMA), and Fox has tried for weeks to convince Lopez to stick for a third round. Still, sources say it’s unlikely that more than one mega-million-dollar diva will wind up at the table. So if the network can land Carey for less than Lopez’s current demands, expect a lot of contestants to sing “Dreamlover” next season.

For the third seat, Fox is considering a lower-budgeted option: Former Idol contestant Adam Lambert, who could bring a sharper edge to a panel that’s been knocked for being too soft in recent years.

Another buzzed-about element to the Idol shakeup is the show’s cost. There’s been media reports (in EW and elsewhere) about executives seeking to cut Idol‘s budget. Sources say that whatever annual budget tweaking might be done, Idol‘s overall production quality will remain unchanged.

Even if the Idol re-organization doesn’t boost ratings, the show is strong enough to survive another 23 percent drop next season. Such a decline would give it roughly the same-sized audience as TV’s second-biggest non-sports program: NBC’s The Voice.