I agree, Kevin. Avengers was successful largely due to the creative efforts behind and around the film. Whedon did a bang up job writing and directing this movie. (Certainly MUCH better than Serenity, and I enjoyed that movie, despite it being another overblown tv episode).
I think I meant to say that generally, Disney did not interfere with the production of The Avengers. They'll obviously be a bit more "hands on" with Star Wars.
I think Walt Disney Productions has done a lot of growing up in terms of movie making. I really enjoyed "Race to Witch Mountain" which was a Disney sci-fi staple back in the '70's, and this recent movie was made considerably edgier. They've also clearly dropped any problems with making movies at a PG-13 level. (Especially since PG-13 is pretty much just the new PG now.)
But I also agree that sometimes they do just swoop in and put their brand on other folks' work. Not that they necessarily do a bad job with it.