Yes, the title is correct. Portal 2 (Beta) is now available on Steam for Linux and presumably available for all of the SteamOS beta testers, though one of them will have to confirm that for us. I started playing Portal 2 on Windows but decided not to finish it until it came to Linux. I’m downloading it now, all 11 GB. It should be finished by the time I finish work.
If you would like to join me, look me up on steam: TJ-Aich.