Gabe Newell from Valve confirmed it via email.
Despite rumors the pioneering game company was working on a new console, and they still haven't finished Half-Life 3, Gabe Newell has become obsessed with getting his digital distribution tool working with the Linux kernel. Earlier this year, Newell brought out experts in the open source operating system begun by Linus Torvald to show off Left 4 Dead 2. Newell was excited for Linux, and even moved his desk at the Valve offices next to the team working on the native Linux Steam client. We will see the fruits of Valve's labors sooner rather than later, as a fan sent a simple email asking whether Steam would be on Linux by the end of the year.
Gabe Newell's one-word response was, "Yes."
There you have it. Steam on Linux in 2012. Now that's a platform I can get behind.
I haven't experimented with Linux myself, not having the chops (or the time) to get it working with my PC games. But if Linux can run Steam natively, I may just make the switch.
Then I will be a real hacker!*