Well apparently depending on what quests you choose to do, and which characters you use the most, you can create a team and name it, and you can get different endings.
"Change the course of the game –The missions you accept, and the objectives that you meet, will have a direct impact on how the story plays out. At the end, see how your choices changed the fate of the Marvel universe."
So it prolly isn't completely linear, and prolly has a good replay value.
THE JACKEL