Well, it's official, there's a new beta. They had open signups, and it apparently filled up. Fuck!

http://store.steampowered.com/app/260/

Press release:
Available immediately, Valve has launched an extensive update to Counter-Strike: Source, now in beta.

The update includes a host of new features and functionality developed in collaboration with Hidden Path Studios. These include 144 new achievements, a new domination and revenge system, player stats, and more.

This beta will run for a limited time, and once complete, the update will be deployed to all Counter-Strike: Source owners for free via Steam.

Server admins may download the dedicated server files via the HLDSUpdateTool using "-game cssbeta" in the command line.