Today,Tweetmeme expanded its offering with a pair of new features aimed at making the site more sticky. The first is a tag cloud, which analyzes the shared content, finding other words that Twitter users have included in their tweets, and displaying them below the items in their "popular links" page. The second is a leaderboard, which highlights those Twitter accounts which have most frequently been the first to share the most popular links.
In terms of determining influence and popularity, you've always seen a push/pull between enabling a gatekeeper with the power to move items up and down, and letting the crowd decide. Tweetmeme believes solely in the crowd - even featuring the total number of times the item was shared. Today's top shares are in the 400 to 600 range through all of Twitter.
Accounts on the leaderboard aren't much of a surprise - including RSS feeds for TechCrunch, Digg, popurls and ReadWriteWeb, for example. Additionally, the cloud below each item is tempting to click, but not functional. In theory, it'd be good to click on an item in the tag cloud and see other shared links that have the same tags. Maybe that's coming, but it's not yet here.
You can catch up on the most popular items, as determined by Twitter, at http://tweetmeme.com/.