because with the current attention that marvel films are getting if this doesn't live up to the hype or the high standard that has been set by the Marvel Cinematic Universe films during Phase I and the start of Phase II then it could spell the end of Foxs involvement in the franchise.
I can agree with this. It's a tall order for that storyline, and they're on thin ice after all the shenanigans with Wolverine movies. But if they can pull off something that would reach the bar for what we all now expect from Marvel (honestly, the Iron Man movies and the Avengers have set that bar enormously high now), then it should be good.
They should be fine in terms of canon so long as they distinguish this is separate from the other movies' canons they already released. But if they somehow try to tie it all in, I get the feeling it will be terrible. >.<