I suspect it's going to be a lot like the desktop situation: there is no reason to leave Windows for Linux. Especially considering gaming enthusiasts are a lot more sophisticated than just e-mail and browser folks.
There would need to be a successful SteamBox to get those numbers to budge much.
In terms of discrete GPUs it's amazing how much of a lead NVIDIA has over AMD.
Marketing, exclusive OEM contracts, review shills and fanbois keep people on Nvidia like they keep them on Intel, even when they aren't making a superior product at the price point of their competitors.
We can already see where their market dominance has lead, $1000 GPUs and $1200 CPUs are back at the high end.
I'll take 90% of the performance at less then 40% of the price.
Just to clear things up a little, this is a survey, there's nothing automatic about it; they literally ask a small group of Steam users each month to submit to the survey.
Unfortunately we're in the dark about the exact methodology being used, depending on how users are selected for the survey the results may be skewed in either direction, and there's also a question about how they round the results.
Just think: if the survey was given to 1% of the world during one hour once every month, depending on what hour they pick they may end up with very different results as different countries would be asleep and some countries use Linux more than other countries.
I'm not saying that this has happened, but that it would be very hard to write a manual survey that avoids these biases. If the survey was automatic and real time, I'm sure everyone would be up in arms about their privacy being violated.
That would be a very stupid way of doing it. Doing an OS check when you log into the account however is a necessary task that would be counted. You have to do this to allow your client to know what games in your list can't be installed on your current OS. Most people that tied their HIB games to Steam know this since there are quite a few that haven't been released on Steam for Linux even though they are on Steam for Mac and Windows and have a Linux port.
Personally I've got 64 games registered with Steam, but only 48 are playable. Though I own several more on Desura, personally I'd rather support the underdog in this fight. Whats nice is Legend Of Grimrock finally popped up in the list, which means access to all of the mods hosted on Steam for it, what's not fun is that Dear Ester hasn't popped up yet, they are still doing the native port, the version on the HIB servers is the Wine wrapper version they did a while back before the version of Source they use was ported by Valve.
They didn't support linux for years, yet people ran it on Wine.
No doubt there will be some people crazy enough to run it on BSD, Haiku, some old Win/Mac, etc.
Doubtful. Anyone using old Windows would also be using old hardware due to lack of drivers and as such would be limited to old games, thus Good Old Games would be the far better option for them. Old Mac on the other hand, Steam doesn't exist for non Intel Macs, never has and never will since PPC is an incompatible CPU architecture, Rosetta only allowed Intel macs to run PPC software and very few Mac games where made universal binary due to hardware limitations, since the fastest GPU you can fit any PPC Mac with was the 7800GT, you could make these work on the G4 towers by getting the rare 7800GS AGP cards and flashing their bios with a modded 7800GT Mac edition one, but there was a risk of bricking if done wrong since the PC bios is only half the size of the Mac bios and as such you had to be careful about what card and what you cut.