I'm an undergrad at Berkeley, so of course I've got some opinions.
I have to wonder if the number one goal here isn't attracting new students... Be warned fancy computers look like old slow computers very quickly.

My favorite labs to actually work in are our SunRay thinclient labs, solely based on the fact that the machines are silent. They aren't just quiet. No hard drive, no fans, no noise.

All the grad students here work on laptops. Virtually none of the undergrads do. I'm not sure, why, or if your dynamics are the same. Nothing makes a laptop more practical than 802.11b wireless. And power outlets.

Bean bag chairs would make it dificult to type while using a computer. Flat panel displays are nice to look at. Good keyboards that you budget to replace frequently are important.

Music in a lab is counterproductive. At any given time half of the people will hate what's playing. Any while we're at it, kill the damn PC speaker that beeps whenerver you tab-complete something in bash.

Can you avoid flourescent lighting? It'd be nice if you could.

It seems we're talking more of a break room than a place to really get stuff done. To that end, table space without computers on it is important. So is allowing food. (You'll have to replace those aforementioned keyboards a bit faster, but who cares).

Computer wise, I'd personally spend half that amount, and buy brand new ones in two years. The difference between 3 and 2 Ghz is rarely noticable, and intel charges more than a PC should cost these days for their top of the line processor.

Well, that's all for now. I'll chime in later if I think of anything.

Matthew