For those that have doubted the exclusive Phoronix claims for quite a while now that the Steam client and Source Engine are in fact being ported to Linux, the doubts can be nearly laid to rest. Even I began to wonder how long it would take before the clients for their popular games would be publicly released under Linux. However, after confirming the information perhaps a bit too soon, their level of Linux interest is much more clear after spending a day at their offices. A meeting topped off the day with Gabe Newell regarding Linux where he sounded more like a Linux saint than an ex-Microsoft employee. Valve does have some great plans for Linux beyond just shipping the client versions of Steam and their popular games on the Source Engine.
As I have been sharing for a few weeks, Valve invited me out to their Bellevue, Washington offices after Gabe Newell asked me last month for some referrals of developers with Linux OpenGL experience. They already have a team of Linux developers working on the client efforts, but they are looking to expand.
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Also: Why Steam on Linux makes sense *now*