If not aware yet, Facebook has decided to give you a real identity istead of a no to identify yourself. How does this work? Simple , have a look at the below image :
You can decide what you want your facebook username to look like( subject to availability of course! So this was release over the weekend and some really smart people on the web decided to get creative and this is what happened :
Tim Lunsford grabbed http://www.facebook.com/wp-admin, which will make people confuse it with WordPress admin login of Facebook, if they have any.
Joan Desautels grabbed http://www.facebook.com/suggested, which could be confused with suggested facebook users and surely make a few more friends.
Sergei Polishchuk grabbed http://www.facebook.com/readme.shtml, just in case you wanted to confuse it for the facebook service terms or about pages.
Jack Foster got http://www.facebook.com/staff.aspx, which could otherwise have led you to Facebook staff and their pages.
Smart eh! So have you got yourself a username yet? If you havent, you should hurry before your left with a username which is not your 1st,2nd or even 3rd choice 
Source : Facebook Blog & QOT
