Google is really bad at SEO :) What a weird move!
It's amazing how some weird things like this create the real buzz :) There's the reason why we call them VANITY URLs (that's the secret of their success!)
G+ Custom URLS- Now you can send traffic to Google rather than them sending traffic to you. Clever move by Google to increase Plus traffic.
I have no idea why Google would be so slow and careful to give them away. The update is nothing more than allowing more people to have plus.google.com/+YourName that redirects to your profile or page.
In any case, these are probably easier to promote on business cards!
Besides, that's one of those updates when, if you don't have one, you are probably a loser :)
One thing to note is that you may still need your old (numeric) URL to claim your authorship as I've seen the Rich Snippets Tool to have problem recognizing the Authorship markup if you use your vanity URL in there.
As Mark Traphagen noted "Be aware that your vanity URL is really just a redirect to your "real" Google+ URL, similar to some link shortening services. Not all tools will be able to do the translation, so it is best when using third party tools that want to analyze your account in some way to right click your name on Google+ and copy the actual (numeric) URL."