Tweetmeme.com is a service which aggregates all the popular links on Twitter and determines which links are popular. Tweetmeme categorizes these links into categories, subcategories and channels, making it easy to filter out the noise to find what you’re interested in. It is also easy for you to subscribe to each category and the most popular through RSS feeds and Twitter accounts.
Using the Tweetmeme button you can discover new content and tweet about it. The button provides a fully integrated URL shortener and the title of the story or page. Each link which is posted on Twitter adds one to the tweet count for that story. Once the story has reached a critical mass of tweets, it makes it into the top 10 on the front page and gets tweeted by Tweetmeme’s Twitter account.
You can install the Tweetmeme button easily on your website or blog, and let your users quickly retweet your stories straight from your site. They have a plug-in for WordPress.