I'm sure quite a few people have heard but steam is pushing a linux based operating "Steam OS" The Steam Universe is Expanding in 2014 It'll be primarily for a living room style build and will also be used for streaming games from your current PC. This is along with their other plans like family sharing and such. Depending on prices, steam boxes could be a good "my first gaming pc" for people.
It's an interesting concept, as long as they dont market it as something to compete with the Xbox / Playstation it could do quite well. At the moment the main problem is the lack of games for Linux, however that could change given that since Steam landed on OSX a fair few PC games were ported over, which could be easily ported to Linux too, as Valve have done with games like Half Life 2. Price would be quite a big thing too as you say, given how you can build a good gaming PC fairly cheap these days.