Until now, that is. E! News confirms that The Voice stars Christina Aguilera and Cee Lo Green will be participating in this sure-to-be memorable event along with a couple of others...
Although it'd be super cute if Blake Shelton and Adam Levine also joined in so we'd have the whole NBC series involved, they're not—at least not yet anyway.
Two other artists that will be taking part in Michael Forever—The Tribute Concert on Oct. 8 are Leona Lewis and the band Alien Ant Farm (might sound odd at first, but remember, they did a cover of "Smooth Criminal").
No other announcements have been made, but what do you think so far? Who else would you want to see or expect to participate?