I really don't know when it'll be out, although footage to date looks pretty far along so I would be surprised if it is too far off, sometime in mid/late 2011 most likely.
At the end of the day though I can wait as long as needed. I want them to release it when it's ready.
FFXIV is direct proof of what happens when you rush a release. Far from help their bottom line, SE have generated a raft of bad press, turned people away before the game has even taken off (no doubt permanently in many cases), wracked up review scores that will put people off of trying the game even if they fix all of their core issues, and ended up having to extend the free trial period anyway. They wanted to be a real challenge to WoW, but I just don't see it ever happening now.
The quality of an MMOs release is so important these days. Get it right, and you're onto a winner. Get it wrong, and your can't rely on your reputation to save you.
I really think ArenaNet have the ability to get it right. So, as much as I want to start playing right now, I'll wait as long as it takes :)