well here are some thoughts on some groups who people want added:
The Police: big announcement monday. i dont see it having anything to do with coachella. i think they have their own agenda and are gonna rake in the dollars so they dont need or probably want coachella. it would be nice, but i dont see it happening. chances: 15 percent
Prince: this could be longshot but it would fit the madonna type vibe they brought last year. prince is in vegas so he is close to indio. he could play the sahara tent or be moved to headline friday. prince does things his way so he could or could not. its a pipedream but it is out there... chances 30 percent.
Nine Inch Nails: the only way i could see them performing is if they want to a special gig in the sahara tent or something different than the main stage. album timing is there. but its doubtful. chances 20 percent
David Bowie: he was on alot of people's wishlist but it just doesnt look good at all mayb next year. chacnes 10 percent.
foo fighters: could we see a special acoustic set somewhere? maybe... chances 35 percent.
Incubus: another longshot but could be added. but they might be too mainstream to not headline and still play. chances 20 percent
Eminem: this could be one of those last min additions. would be interesting and he says he is ready to come back out so we shall see. chances 35 percent.
personally the lineup is strong but if they want to add some bands just to add them, hey on top is some that i think would be compelling. we shall see!