Facebook started rolling out a new site design on July 20, 2008 for users to preview and test the functionality of the site. The new design has been under testing since the beginning of this year, and more than 100,000 Facebook users have participated in user testings which led to many layout and features included in the final version.
The profile page comes with a single status feed + the wall, with additional info and photos pulled into separate tabs. All the applications have been grouped into the Boxes tab. The users can add additional application tabs as required (similar to iGoogle fucntionality).
Tabs should address the insane load-time with many profiles, but the added benefit to Facebook is that there are now more opportunities for them to display ads - so it's a win-win situation for the company as well as the user.
You can check out the new design at www.new.facebook.com