Onlin [e] Guid [e]

Till now, when you open someone's facebook profile, you see some thing like "id=592952074" in the URL. But that's gonna change now. Instead of that ID no. u'll be able to display your own username!
Using this you'll be getting a kind of Webpage of your own on facebook. Thus it'll be more easy for people to connect with you.
See the snapshots
You can get your username June 13th onwards from this link www.facebook.com/username

I think facebook was inspired by sites like twitter to do this because it also provides similar facility!

More details Here