Re: Who dies?
Nobody dies in AoU, but in A3 Whedon will go buck wild and kill off every single Avenger. It's canon. Just read (or re-read) The Infinity Gauntlet. But no worries because they all come back to life at the end. That's canon, too. That's also called having and eating your cake and would be the apotheosis of Whedon's career.
"Don't touch Lola."
Coulson's Army: Stronger than Death