Valve are hard at work on porting Steam over to Linux, but it looks like the company is doing well enough with the software to release a beta version of the app on the open-source operating system. Valve are looking to release an internal beta sometime next week, and after that, we're looking at an external beta limited to just 1,000 people as soon as next month.
The limited beta will sport support for Ubuntu 12.04 and above, with access to a single Valve game. There's been no word on which game it would be, but we're probably going to see it manifest into Left 4 Dead 2, which is something that the company has talked about using so far. The results of Left 4 Dead 2 on Steam saw it running a tad faster on Linux under OpenGL versus Windows on either OpenGL or DirectX.
Valve will open up a sign-up page for the external beta in the next couple of weeks, where they'll select beta testers based on the hardware they're running. Valve are wanting to test Steam for Linux on a variety of different setups.