The Planet Hulk angle would lead to his essentially being a villain - and a green CGI one for the duration. Then again, why not have Avengers 3 be a battle against the Hulk & a space army? Yeah...then again...probably not gonna happen (the plot the article mentioned, not a Ruffalo as Hulk flick - that would seem to be a given post-AVENGERS)
Of course, they could use the Planet Hulk story as a loose inspiration to get Banner in space, esp if Marvel wanted to perhaps cross pollenate the AVENGERS & GUARDIANS OF THE GALAXY films. Bryan Singer looks to be doing kind of the same thing with XMEN - loosely (I assume) adapting the Days of Future Past story arc - for the follow up to XMEN FIRST CLASS. At this point it sounds like he's got just about everyone from both his/Ratner's original cast & Matthew Vaughn's (save for Halle Berry) on board.
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