Advertise On Twitter with Tweetup - an advertising network that works similar to AdWords. So where do these ads show up since this is not Twitter's official platform?

TweetUp’s sponsored results will show up on partner sites such as Business Insider, Answers.com, and PopURLs, and on Twitter platforms such as Seesmic and Twitterfeed, among others. When there are no paid listings available for a search, TweetUp will show users and messages algorithmically, relying on help from Klout.com’s rankings and analytics. via sel