Call Me Kreskin
In the spirit of calling things, I now look to World War Hulk and pretty much figure out that... yeah. This is the Warbound's fault.
Specifically, Miek and "Brood Creature 2 of 6" (or so the Planet Hulk hardcover tells me) as around Incredible Hulk #103 went into the pod that lunched the Hulk into space to... touch carapaces or something. My apologies, I only lightly followed the prequel series ot World War Hulk, something I'll get to in a second. So, anyhoo, they find the recording of the Illuminati that was part of the ship's systems after lamenting that 'Holku' is forgetting what a terrible engine of destruction he was throughout the rest of this storyline Now that the evil Emperor is dead, he's got a wife and kid and seems to be making some shot for peace in this crazy mixed-up world he's now ruling, Miek watches the recording and realizes that this could help him "remember".
So, my guess is that he and the Brood rigged the thing to explode. Now, whether or not the rest of the Warbound are going to be in on it is probably not likely and the two buggy aliens will take the fall for blowing up everything the Hulk had ever created in his life. The tradgedy and betrayal will shake the Hulk to his core, make him realize that he'd been just as used as Banner ever was and cue the sad piano music and the man makes himself scarce after everything he's done. Obviously, there's a red Hulk to sort out and the direction of the two Hulk books to hash out, but I don't think they are going to pin the death of Sakaar on the Illuminati. Sure, they're jerks, but rigging the pod to explode should be too far for even them.
Not bad, as far as the Hulk mythos goes and really, this should put things back on even keel between Banner and his monstrous alter-ego (or should it be the Hulk and his puny other-half?) and set the stage for the right stories to be on the shelves when the movie hits. It will also allow for a Warbound mini-series as the two traitor will have to be dealt with and I'm pretty sure the Hulk will have washed his hands of them after all this. The heroes can go free and get back to what they've been doing for the past how many issues in their own books and the only real shake-up of the series is self-contained.
On the other hand... this would really suck for people who hadn't read Planet Hulk and have no idea for the motivations of the Warbound. It's a little like Loeb's trick of introducing a new character and then revealing they've been behind the villainy of the story they were introduced in the entire time.
All I know is that after tomorrow, World War Hulk will be over and I hope to high heaven I never have to see the Sentry sit on the damned couch ever again.