E3 is like going to best buy in 2 years, and instead of there being a couple games there, there are a thousand, and instead of a few employees helping other people, the people who made the games come up to you while you play and tell you how to play. Not only that, they get excited when you enjoy it, they feel guilty when you get stuck, and some of them really care what you have to say after you play.
Of course I tend to avoid the games with massive lines and just sneak back and forth to whatever is open. The line to see the Wii was insane, when I finally got to the end there was a guy with a sign that said "line closed"
I put some screens and a discussion of my experience with Idea Games here (and in subsequent posts), the most exciting thing I got to do there.
The conferences and panels were very interesting too, all of my ideas about what is changing in gaming seemed to be on the minds of developers, publishers, and distributers as well. Yes distributers, apparently its realistic to expect wal-mart to want to make its own steam client, or something like direct2drive at least, so they can keep selling games when we get too lazy to go to the store.
My PICKS
The BEST of E3

Just Cause - more here
The WORST of E3

OK I never played it, I just noticed people avoiding it like the plague and thought it was hilarious