To add to the other comments, from the very beginning they had a tux on the kickstarter page.
The Oculus 0.2 and 0.3 SDKs didn't really support Linux at first but as the source code was released, jherico fixed it up and linux support got integrated.
> The Oculus Rift and the Oculus SDK currently support Windows, Mac OS X, and Linux.
Most of their 0.4 SDK source was still available but they had already started with putting their optical tracking into a closed source binary, which took them quite a while to release for linux, but eventually they did.
> Our development for OS X and Linux has been paused in order to focus on delivering a high quality consumer-level VR experience at launch across hardware, software, and content on Windows. We want to get back to development for OS X and Linux but we don’t have a timeline.