Update: I just saw that Tinic Uro has a great post about the release. His intro:
To quote someone well known, 'hell froze over' and we finally released a beta of the GNU/Linux version of the Adobe Flash Player 9 (look for the "Linux version" download link). It did take more to get to this point than you might expect. And no, Mike is not the only engineer working on it. Currently I count 6 engineers working on the GNU/Linux platform, even more have GNU/Linux boxen and/or VMWare images now. And there is still a lot of work left to do before I consider this penguin version not a beta anymore.
It is only the 32 bit version. I've been trying to track down information on a 64 bit player but haven't gotten anything tangible yet. I would love to get the response from the Linux community about the new player once you grab it. Are you using it just to watch videos that require Flash 8? Are you checking out Flex 2 apps? Leave your thoughts in the comments.
(note to the update: Tinic also mentions 64 bit - "What about 64bit? There is no Windows 64bit or OS X 64bit version either right now. As I said before it is not a question of 'recompiling' the source code, there is lots of generic non platform specific work which needs to be finished first. We will ship a 64bit version for Windows, OS X Leopard and GNU/Linux. It will happen. When? ... When it is ready."
This is a big milestone for Flash. I know the Linux users have felt like second class citizens when it comes to Flash, and that they were skipped for an entire version. Finally, with the release of the beta, Flash is cross-platform. Hopefully this will prompt Microsoft to give some WPF/E info.