Director Lewis Leterrier had this to say about the Hulk VS Abomination fight:

“This sequence [Hulk vs. Abomination] is toward the end of the movie. But our final scene, our final battle – unlike a normal movie where the final fight scene is six minutes long, ours is 26 minutes long! So you get 26 minutes of two monsters pummelling each other through New York City, jumping up and down, ripping helicopters from the sky and stuff.”