As expected of a beta, you can't install the .deb package from terminal. There's a whole bunch of package dependencies that you need to install. The simplest solution is to double click the package and let Ubuntu Software Center handle the rest.
The initial installation through Software Center doesn't seem to tell you much but behind the scenes the Steam .deb file adds Steam's repository to Software Sources, updates your package index, and installs all dependencies for you. In my case something crashed in the process and Steam got installed in the confusion before I knew what was what. It's most certainly an experience that needs much improvement.
|Updating Steam after installation|
On first launch, I got a blank Steam window where I was supposed to be able to login, or create a new Steam account. I had to kill off the client and re-attempt before I could finally get in on the action.
Installing Team Fortress 2
|Steam's main window|
It's a pretty hefty download so it could take a while depending on your bandwidth.
You'll want to install the latest AMD Catalyst Beta (12.11) drivers to run this game. I tried with the proprietary driver installed through Ubuntu's driver installer tool but the game doesn't start.
The downside to using the Beta driver is, of course, the AMD watermark on the bottom right corner of your screen. The game plays just fine with it though.
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