The Incredible Hulk sticks out like a sore thumb in the franchise. Not only the fact that Ruffalo replaced Norton, but their hulks are completely different in design and personality. The only thing connecting TIH to The Avengers is Stark's appearance at the end, otherwise, it feels like it doesn't fit in with the rest, you know?
I didn't really care for TIH, so I almost want to discount it from The Avengers canon and consider it stand alone. I know it is apart of the canon, but it doesn't feel like it.
In some ways, it feels almost as disjointed as the last two batman films were to Tim Burton's first two; where while the design, most of the cast, and tone of the films after Burton's were completely different, they were still a part of that continuity.
Or heck, a better example would even be on how SR is supposed to be treated as a sequel to S:TM (SII not so much)
And yeah, TIH is like the sore thumb in the MCU, it's like the only film not mentioned whenever someone official recounts the success of previous Marvel films, and it was the one to perform the lowest at Theaters and receive the lowest score on RT as well. Not to mention that out of all of the films going into TA, the events of TIH had the least impact in how the events of TA started out with.
I was surprised at how many references to TIH there were in this movie. I kind of expected them to sweep it underneath the rug after Norton got recast, but not so.
Yeah, I remember Feige saying not too long ago that despite Mark having replaced Ed, that TIH is still very much in canon with the MCU and that Mark's Bruce is still the same Bruce that underwent that experience.
Heck, in some ways, if you weren't a fan of TIH's take of the Hulk, you could easily ignore it from your memory when watching TA, or if you're one of those who enjoy continuity, there's still room to trace them back to each other.