I feel like Hulk will be temporarily back benched for the sequel but might still figure into the climax of Avengers 2 when the team needs him. He's a brilliant scientist and could cameo throughout as a lesser character working on some stuff back at HQ, give them some information, and then be done with that scene. I'd be happy, as long as they use him in another marvel movie at some point in the future (I think Feige is masterminding something...).
Why would Marvel toss away movie Hulk for a tv show in a different continuity? Now, when he could potentially get his popularity back through a movie that seems like it will be very Hulk heavy. Sure it's got Thor's villain, and Cap/Iron Man fighting for leadership, as well as the Cap adjusting angle. But they'll have to refocus on Banner to reintroduce him, especially under a new actor. And then we think Loki controls the Hulk somehow or for some reason Hawkeye takes him down when we have Avengers vs. Hulk. Then there's probably Hulk vs. Loki by themselves, Hulk vs. Loki's minions, any time Hulk transforms we don't know of... And most likely helping in a final battle etc. etc. It's also heavily about Banner being recruited and him being the outcast, and a liability, and his whole redemption arc. And Shield probably telling him what to do. Really the other Avengers are already pretty much with Shield (for the most part in Thor's case once Coulson vouches for him and he stops fighting Cap)
How many battles do you think Hulk will be in? I think we'll see a ton of Hulk in action. And tons of Banner too. Maybe enough for them to keep him on-call during the sequel, since he's already going to be transforming a lot here. And the cgi is expensive. A lot of the craziest action is going to be when Banner transforms. He could still show in the final battle of Avengers 2 though to cut down how much they would have to use him. They call him up in the middle of the night and say sorry dude these masters of evil are harder to fight than they sound. And he shows up to give them extra support. I bet Banner will still want to go without incident, and will be reluctant to use his "talents" unless the Avengers really need him. Even though he may have more control over the hulk and more of shield's confidence. I'm thinking his spot in the main four is filled by a more active member by the time Avengers 2 happens, but that Banner/hulk's still gonna show. Just not be focused on. Or completely part of the current team. Just do his ass kicking biznass and then turn back to Banner to fade into the background.
What if the show fills the spot of solo movies for Hulk? And Banner is played by someone else, but set more or less in the same continuity. Giving us what Hulk's been doing until the Avengers need him again, or if they decide to use him in a future Marvel movie. That way he's still out there and they could possibly move the character back into the movies somewhere down the line. At the same time creating opportunities for other franchises/characters that fail as movies, edit: or fail to return in the movies, to launch or cameo in the Hulk show.