Valve has rolled out a new beta version of Steam today which completely overhauls the look of the digital distribution service and gives the store and community features an entirely new interface.
The beta is currently opt-in only, which you can do by launching Steam and downloading the '2010 UI Update'. More information on how to do that is available on the official update page
The new UI seems to have focused on providing more community information and features to players, such as letting you know who on your friends list owns a game via the Store page - so you can judge it before you buy it.
Other new features include a refined news feed, which keeps users clued in on recent releases, updates and sales without all the pop-ups. There's also increased support for achievements and the ability to organise your games library into lists, such as 'Games They Play on the Bit-tech.net Server
There's a bunch of new tweaks too, such as more easily read fonts and info about download rates when you install a game. You can check the full feature list on the official site
How long the update will remain in beta is currently unclear, but in the mean time you can drop into the forums
and let us know what you think of the new look.