Not surprising since nVidia is heavily invested in Android in the mobile space.
Edit: More to the point, SteamOS is going to have some major issues when it ships. Namely that the PS4 and Xbone will both have more feature complete OSs that'll let me use things like Netflix, Crunchyroll, and Amazon Instant Video out of the box. Whereas, IIRC, SteamOS won't support any of that when it's released. So SteamOS supports games, that's... Ok I guess? Yes, SteamOS will get streaming apps, etc. but it will take quite a bit of time for that to happen.