Nortons Hulk is directly referenced in the Avengers movie when Banner talks about trying to put a bullet in his head but “the other guy” just spat the bullet out. The abomination and General Ross are the other links.
The movie isnt as bad as people make out, its better than IM 3 or Thor 3 but yeah the rights are weird.
Incredible Hulk also has an appearance by Tony Stark in the post credits scene.
I remember liking Incredible Hulk when it came out. I think it's certainly on par with some of the other MCU fillers. But I have to admit I haven't seen it in over a decade (a decade? Wow.).