If you are active on Facebook, there is very less chance that you missed on the recent Facebook UI update “Social Graph” or more popularly referred as “Timeline” (a screenshot of how the Timeline profile UI looks, here below)
This Timeline UI has been quite popular and is supported in most of the modern browsers including IE9, Chrome 14 & Firefox 6 and above.
I am a power consumer of web and use IE9 as my primary browser. Timeline UI works excellent in IE9.
I have also downloaded the IE10 Platform Preview for Windows 7, which provides greater support for some of the HTML5 standards.
Also, with Windows Developer Preview ships the IE10 Developer Preview (a newer version after IE10 PP2). This has the best possible support for CSS3 transitions and other latest web standards.
Both in IE10 PP2 and IE Developer Preview, Facebook Timeline UI doesn’t show up. It shows the classic view although I have enabled timeline. Gut feel is, they are doing browser sniffing and with the user agent not enabling the Timeline for not matching major version 9 in case of IE. Actually IE10 PP2 and Developer Preview have better support for CSS3 and other new web standards. So, to enable Timeline UI in IE10 PP2 or the IE Developer Preview shipped in Windows Developer Preview, we need to use the IE Developer Toolbar (press F12)
So, here is the view of Facebook Profile in IE Developer Preview which features by default Browser Mode IE10.
Once we change the browser mode to IE9, I get the social graph view as below
I tested the same in both IE10 Developer Preview (Windows Developer Preview) and IE10 PP2 (Windows 7) and got the desired results 
Goes on to prove my earlier posts on how the Developer Toolbar in IE is very helpful for Developers.
And here is a nice video on how to enable Facebook Timeline for your account.
I think it is these little nifty changes that separates we developers from the regular consumers
Cheers !!!