The film rights to Spider-Man were owned by a different studio to the one that does the Avengers. Now they can exist in the same shared cinematic universe, due to a deal.
There, not so hard.
Okay so I presume the Avengers are really brilliant and well worth having in a film, great.
How will all of this make the next Spider-Man film better than when the seeds for some Sinister Six stuff was being hurried through the plot of The Amazing Spider-Man 2?
One way or another it always seems like the priority is to shove in loads of super villains or super comrades rather than simply get the knack of making a decent standalone Spider-Man film or three.
Also it seems that the release date for the next Spider-Man film is mid 2017, yet aren't they planning to shit out an MCU film featuring Spider-Man before that? I'm confused.