An update to the Counter-Strike: Source beta and Steam client has just been released. Steam will update itself automatically when you restart. Here is a list of the changes:
COUNTER-STRIKE: SOURCE BETA CHANGES / ADDITIONS:

• Improved server changelevel behavior


• Improved behavior of full servers


• Improved "say" behavior on servers


• Addressed SetMode() issues


• Addressed "Invalid property: DT_BaseAnimating" issues


• Can now create windowed modes at the same size as the desktop


• Changed sv_pausable default to 0


• Improved command line parsing


• Improved change team binding


• Improved centerprint ID behavior


• Disallowed command "overview_mode" if not in observer mode

STEAM CLIENT CHANGES / ADDITIONS:

• Improved pending subscription behavior


• Improved 'reusing credit card' warning during purchase


• Changed credit card expiration year selection to go up to 2014


• Improved display of "not enough disk space" message in game install wizard


• Improved purchase wizard timeout behavior