Google announced adding an additional method of verifying your site with Google Webmaster Tools. In addition to the HTML file, META tag inclusion, and DNS method of verification, you can now use Google Analytics code.
This specifically works with the new asynchronous Analytics JavaScript code but everyone should use that code anyway.
The process is simple. Set up the special code on the site, then go to Webmaster Tools and verify the site. You must be the administrator on the Google Analytics account associated with the JavaScript snippet for you to continue to see that site in your Google Webmaster Tools section.
Here is a screen capture of the current available methods of verification:
Forum discussion at Google Webmaster Help.