Twitter – How to add a retweet button to the WordPress blog

Wordpress uses gravatars just like StackExchange sites source. Gravatar uses a hash of your email to identify you and return your avatar. By providing your email (same one you use here?), that's all Gravatar needs.

Other than trying to do a search on Google or your preferred search engine, I don't think this would be possible.

This should be exactly what you're looking for: Offsite Redirect provided by WordPress.com