Based on this tweet from Nigel it looks like we'll be hearing some Kelly this week...hopefully it's not butchered. I'm not sure which songs, but I'd guess from either AIEW or Stronger because he tweeted a few days ago that the theme this week is 'This Decade', meaning 2010-2012.

Nigel Lythgoe ‏ @dizzyfeet
I love the Gotye song. It makes a great duet on #AmericanIdol this week. How wonderful and ironic that we're doing 2 Kelly Clarkson tracks!