I don't find Windows to be a hassle (I find it less of a hassle now it's stable), you can turn off any annoying security features. Heck, I am even a fan of Windows 8.
However, I don't have a problem with Linux either, I have a dual boot with Ubuntu. I think it's great more games are going Linux and I would love to see it become a lot more popular. I think competition is healthy for the market. The thing I also like is that more development tools are being directed at Linux, we've always had the Torque Game Engine and I see Unity3D now supports Linux (though there isn't a Linux version of the editor, but they didn't always have a Windows version either, so who knows?). I know there's people who'd like to see AppGameKit supported on Linux as well. If Linux was more popular, I am sure TGC would consider it.
I think it's a step in the right direction for Valve and I hope they encourage more folks to develop for the platform.
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I've installed Steam onto my Ubuntu partition, it runs pretty smoothly, sadly not many of my games are Linux compatible though.

Out of my collection, VVVVVV, Counter Strike: Source, Beat Hazard, World of Goo, Bastion and Book of Unwritten Tales work. I tried World of Goo so far. If they get enough support from developers, I'm sure having Steam on Linux would be worthwhile.