User blog comment:HombreHormiga/FOOOOOOOOOOOOOOOOOOXXXX!!!!!/@comment-3317214-20130524005311/@comment-1005679-20130524050129

The primary reason I don't think option 3 will happen is that neither Fox nor Disney/Marvel will want to strengthen the others' franchise and if the Avengers were to basically endorse the X-Men movies, there's no way Fox would give up those movie rights

all of that being said...I kind of hope it is 3...i really love Avengers/X-Men crossovers