The lineup isn't due until next week, but it appears Eminem, Arctic Monkeys, Skrillex and Kings of Leon are among Lollapalooza's headliners this year.

In a sign of just how mainstream the Chicago festival has become in recent years, Chicago Tribune's Greg Kot cites industry sources in revealing the acts which will top this year's bill.

Eminem (2009) and Kings of Leon (2011) have previously headlined and are no strangers to the top slots, but Arctic Monkeys would assumedly be making a big leap after their 2011 afternoon set. Meanwhile, Skrillex also debuted at Lolla in 2011, but his recent (and growing) popularity in electronic music has evidently propelled him to the top of the nation's biggest fest.

It's worth noting that the final lineup will likely differ slightly from Kot's projections. Last year, the music critic revealed several acts expected to rank among Lollapalooza's top tier, including The Killers and Mumford & Sons. Ultimately, The Cure and Nine Inch Nails also showed up at the top.

Tickets for this year's event, which is set for Aug. 1-3, go on sale next Tuesday.