I've been here for just about a year now, and have actually seen the live chat up a couple of times. Not rescently mind you, but I even got a chance to use it. As I recally they turned it on when support que was down in 60 or 80 and it was late in the evenning.
It makes sense that they're not going to turn it on when there's a heavy load as it is now - that wouldn't be fair. But don't give up faith, I think we'll see it back in action eventually.