Oh sorry about that. If Spidey was to become an Avenger would that make him part of it?
A new interview from Andre Garfield(Peter Parker) on The Amazing Spider Man 2That's not part of the Marvel Cinematic Universe...
Unless that article mentions how Sony's letting Marvel Studios do a cross-over or something, but that doesn't look like the case according to that article.
It would be up to Sony, since they have the movie-making rights to Spider-Man. Fox is apparently letting them use Scarlet Witch and Quicksilver, who are X-Men characters but are also usually associated with the Avengers, MAYBE to help tie back to their movies, so who knows.
How about the Skrulls as villains of the third movie, with Thanos commanding them or something?
And what about a Deadpool movie? That would be amazing. (also a much better choice than Ant-Man)
Skrulls were originally planned to be in the first Avengers movie, but they are associated with the Fantastic Four, the movie-making rights of which are owned by Fox, so instead they were replaced by the Chitauri.
Deadpool is also associated with X-Men, so again, it's up to Fox to make that happen. And if they do, let's hope it's better then how it was in the first Wolverine movie.