We've covered the Boxee social-networking media center application before, including the recent release that runs on the Apple TV. Now yet another alpha has been released that adds a long sought-after feature: internet flash video playback for "Hulu, CBS, Comedy Central and MySpaceTV." Other updates include improvement to UI performance as well as the ability to add your own RSS feeds manually, including those containing audio and video payloads (i.e. podcasts). This naturally opens the door to considerably more content for your Boxee device, whether it be a Mac, Apple TV, or even, perish the thought, an Ubuntu Linux machine.
Unfortunately, Boxee remains invitation-only. However, you may register at the Boxee site to receive a future invitation.