Updates to the Steam Client have been released. The updates will be applied automatically when your Steam client is restarted. The specific changes include:
Steam Client
You can now join the Friends Beta via the Friends button inside of Steam.
The Steam hardware survey has been updated, with improved detection of graphics card hardware and sound card detection. Results are available here
Added System information help menu option which shows the hardware information detected for the survey
Fixed offline mode not working for users who account names that are all digits with leading zeros
Fixed actively preloading games showing as paused in the mini-games list
Fixed case where store page could become stuck displaying 'loading...' and never show a page
Source & Half-Life 1 Engine
Enabled Friends beta
Fixed several cases where the server browser would not correctly handle filtering of mods
Source Engine
Improved filesystem throughput - this fixes a bunch of stutter reports in Half-Life 2
Counter-Strike
Fixed menuselect 10 exploit allowing players to spawn into game in spectator mode