I believe it's 3 gigs on the PC version.
Though some of that might be borrowed from other Source games, so it's faster if you have other Source games installed already.
Also, these demo files will go towards the full game when you buy it, so downloading the full game won't take as long.


LEFT4DEAD411.COM
Bet with disolitude: Left4Dead will have a higher Metacritic rating than Project Origin, 3 months after the second game's release. (hasn't been 3 months but it looks like I won :-p )







