Google has been rolling out the availability of vanity urls for a little while now. One thing that was picked up by Search Engine Roundtable back in October was the terms. Google actually mentioned they may one day charge a fee.
TechWhack.co posted an article yesterday that included this tip:
If you have gotten yours, here is a cool tip. You do not need to use it with plus.google.com domain. You can use it with Google.com and even Google.me.
Google.me/+yourcustomurl definitely looks better!