Do you think a sequel to the popular (partially because of the Halo 3 beta) Crackdown is being revealed to us this E3?  It's a yes for me, I don't see why a fun game like this wouldn't be continued.
Personally, I really enjoyed the game.  Leaping from skyscraper to skyscraper and when landing you create mini-craters in the ground.  The quest for agility orbs was entertaining as well.