Personally for me the most exciting thing that occurred at E3 was the Metal Gear Rising trailer. It's fair to say that i was incredibly pessimistic about a new Metal Gear Solid game with Raiden as the main protagonist and the general lack of "Snake-ness."  Also the new action orientated theme that was attached to the game, but after watching the trailer I at least know that the "dynamic cutting/slicing," will entertain me for way longer than it should. It's not much, but its enough to get me excited about the game. 
Considering that this is a Metal Gear game I hope that the final product will at least  keep some of the series long running staples such as; eccentric bosses, lots of lengthy cut scenes and/or codec conversations, an absolutely crazy plot and a crazy sense of humour.  
So to summarize, I'm pretty excited about Rising. Plus Raiden's not that annoying.......right?....right? :I