Among other things, one topic of discussion was the return of certain members of the Avengers: Age of Ultron cast. Spoilers ahead for anyone who hasn't seen the movie yet!
A fan asked Feige if Quicksilver, who dies in the climactic scene of Age of Ultron, would ever be coming back. Feige responded, ""Quicksilver is DEAD. 100%, he's not coming back any time soon, there are no plans. No LMD, no escaping bullets, no retcon."
Sounds like that puts the final nail in that coffin. Of course, that's not the end of Quicksilver's onscreen career, as he is presumed to return in Fox's X-Men: Apocalypse, following his breakout turn in X-Men: Days of Future Past as played by Evan Peters.