An update to the currently ongoing Source engine BETA was released tonight. Still unsure on how to participate? Simply add "-beta srcds0407" (without the quotes) to the end of your Steam shortcut command line. See this handy image for about what the shortcut should look like.

Here is the list of changes, including added cheat protection and a DirectX 8 flashbang exploit fix.

* Fixed a server performance problem with queued packets
* Fixed a Counter-Strike: Source flashbang exploit in dxlevel 80
* Game DLLs export ServerGameClients003 for backwards compatibility for plugins
* Only allows mat_picmip to be set to 0, 1, or 2 when in multiplayer and sv_cheats=0
* Cheat-protected snd_foliage_db_loss. Could be used to turn off ambient sounds in Counter-Strike: Source
* Fixed a crash when mashing the ~ key on disconnect
* Fixed a crash with certain materials being blocked from reloading due to sv_pure > 0
* Fixed bug with audio files of different formats overriding the files in Steam where it would use the original audio file's sample rate/format information after pure server rules forced it to load a different file