That's nice. I've been using the following piece of sneaky ghetto code to take advantage of Google Toolbar's URL shortening API:

http://codepaste.net/48qfb7

But now I'll be able to shorten URL's with an official API rather than using a hack. I don't know why Google didn't make a public API from the start.

Now if only they would start using this. Google Maps' permalinks are absolutely terrible for example...

If I tries to shorten the url of http://google.com several times, goo.gl always give back different result. I just wonder will goo.gl merge theses url together sometime later?

This interesting found implies how goo.gl is designed. They prefer writing directly to avoid duplication check and random seek caused by the check. And they though most of the urls are cold so it is not essential to merge them together to keep the hot cache small.

Or they assume nobody wants to play the system in this way. :-)

A few apps have been using the exact same API (though it wasn't officially documented until now) for some time now.

Any insight to whether this would be rolled into a Google Apps for your domain offering?

We're using yourls.org currently for our short domain name and would welcome ($) the opportunity of offloading the traffic to Google's servers.

Does it include the QR generator?

Thanks Google, but we're already happy with bit.ly. URL shorteners were hot a year ago. Now, not so much.