I have to agree, HL2 is definately the next development of FPS gaming.
Graphics and physics and all that aside (we all knew it was good), I'm very impressed on how well they managed to convey, well, what Gordon's going through via a combination of scripted sequences and ai. For example, near the beginning you're outrunning troops and a dude pops out of a door and goes "quick, through here!" After running through the door he closes it behind you, complete with gaurds pounding on the door. The thing is, the dude closing the door is scripted, but the gaurds beating the **** out of you if you didn't run your ass off isn't.
Stuff like that keeps on happening, and so far it's a very effective and therefor impressive.
Oh yeah, whoever's reading this, prepare for spoilerous majoralous.
But to prove that I'm capable of fair and balanced critism, so far the story's pretty fanboy-ish. They keep on tossing in stuff that makes you go "woah, that's cool", complete with Big Brother and all your old HL favorites returning. While I chuckled a quite a lot through a couple dialogue lines, I hope the energy keeps up; stories like this tend to dry up quickly when the sheen vaporizes.
Edited for accuracy. And to save my credibility.