ID Software boss says it has not been a success
Technical director ID Software, John Carmack, has ruled out Linux being a viable gaming platform. Comack told QuakeCon that the the two forays his company made into Linux had not been successful. He said that Valve announcing Steam Linux support changes things a bit but we have made two forays into Linux commercial market, most recently with Quake Live client but that platform just hasn't carried its weight compared to Mac.
Carmack said that while it was great that people were enthusiastic about Linux as a gaming platform, there are not many people who are interested in paying for a game. He added that Linux and open source Integrated graphics were getting better and better. This is because Intel has been completely supportive of open source graphic driver efforts. Carmack said that if he had time he would love to work on optimising Intel open source drivers.
It is enticing to think that there there is a well supported open platform that you can deliver content through the Steam ecosystem, but its a tough sell. Carmack has publicly released the source code to Quake, Quake 2, Quake 3 and most recently Doom 3.