Yesterday Google released to public Post to Buzz and Follow on Buzz buttons. You can choose from predefined list of button templates, how your button will look like and what will be posted to Buzz (description, image, url of website).
With this plugin, you can do all that (and much more), from within plugin configuration page. Besides defining look of your button you can choose where and how it will be placed.
More details and screenshots you can find at http://www.hariscusto.com/buzz-this/