Once in a while an act moves from the outdoor theatre to the main stage the next year(Belle and Sebastian, Arcade fire(I assume) so it is possible My Morning Jacket could do it although they are not on this year's lineup. They were great last year tho! Oh--Interpol also has played the outdoor theatre, sigur Ros has been in a tent and Main stage,Chemical Bros. also.
the arcade fire didn't play at coachella last year.
i'm not really sure what your point is. they didnt play last year but they did play in 05 which is, i think, what momof5 was talking about. the point that 3x5 sunshine made wasnt all that valid either... bands have played 2 years in a row. i'm not saying my morning jacket will be added, but it won't be because they would be playing 2 years in a row.
Missed them at Coachella, but saw them at the House of Blues (Anaheim). i'm a convert. Such a great sound live. In addition to the excellence of Mr. James' voice, the band being super tight is the other major factor. Great energy too. If they're available and there's a good slot open for them, i see no reason they can't do a Bloc Party (05 and 06). If you are on the fence about seeing them, do it (you might be impressed).
One of the best bands out there
and INCREDIBLE live
saw em do a 3 hour set @ bonnaroo (1am to 4am) last year
highlight of bonnaroo i think... well, radiohead was fucking cool too and so was sonic youth
im surprised they havent blown up like whoa