The Google Webmaster Central Blog announced three main changes to verification tool to make it easier for webmasters to verify their sites.

The three main changes are:

(1) A new look for HTML file verification process:

(2) If you use the META Tag verification option and you change your email address tied to that Google account, the sites will now still remain verified. The latest new version of the verification meta tag which is unrelated to your email address. Once you verify with a new meta tag, you’ll never become unverified by changing your email address.

(3) If you use the HTML file verification option, you no longer need to make sure your 404 pages actually return a 404 server status code. Google Webmaster Tools has simplified the file verification process to eliminate the checks for non-existent URLs. Now, you just download the HTML provided by Google Webmaster Tools and upload it to your site without modification. [via]