Will be interesting to see what happens to games sales/usage figures when they release this.

I'm going to guess that most people who are Linux users but are also interested in games will already have a Windows partition that they use for gaming.

So it might be that any increase in Linux gaming on Steam is exactly matched by a decrease in Windows gaming.

I doubt there are many gamers out there who would love to play AAA proprietary games but are holding out until they are ported to Linux.