An even quicker introduction to the final specification of WebSockets: http://socket.io.

P.S. I'm aware that a) this doesn't help anyone not using Node.js on their server (it's not even part of my production stack at work (yet!), even though I'm bringing it to light here) and b) it's more than just WebSockets, for instance it will gracefully degrade on legacy browsers.

I just can't miss an opportunity to sing its praises because it has so many benefits over the simple implementation.