The aforementioned crossover will be entitled "Trial of Jean Grey" and will most likely rely on whatever the heck happens in "X-Men: Battle of the Atom".
Personally I don't think that this is going to be just a two-issue thing. Knowing how Bendis wants to drag stuff around and fill issues with "talkies" this could go for around two issues of All New X-Men and two issues for GOTG with Stuart Immonen and Sara Picheli respectively.
