Well, aside from the obviously impressive engine on display here, I generally think from what we can see it looks more like (what I feel) a Crysis game should do than Crysis 2 managed to.
I quite enjoyed Crysis 2 I suppose, but the small and limited environments and the repeated on-rails sections really didn't fit with the expansive and open feel of the first two games (less so with Warhead than the original, admittedly). At least here it looks like there are some decent open environments rather than corridor-like streets funnelling you to a set-piece arena type of area (with the "stealth" approach all neatly marked on your visor... <sigh>).
Can't say I'll be pre-ordering based on this, but it does give me some hope we'll see more of a proper Crysis feel to the game (and, yes, I accept it's going to have too many sections with aliens and they're going to become at least somewhat tiresome, that's just par for the course...)