You must have got the vanity URL for your Facebook profile by now. If not, then check how you can get your username in your Facebook profile to get a brandable profile URL.
One interesting fact about the Facebook vanity URLs is that, like Gmail, the period (.) is insignificant in the URL. so the username mayur.somani and mayursomani are identical.
As you probably already know, you can have only one unique Facebook profile URL for an account. But since you can place any number of periods at any place in your Facebook URL and it will still work, you actually have many Facebook profile URLs.
Thus, for me, both http://www.facebook.com/mayursomani (no period) and http://www.facebook.com/mayur.somani (one period) will work just fine.
So, how many Facebook URLs do you have?