The most popular links on Twitter
TweetMixx from the well known service Mixx, provides the latest trends across Twitter by showing the hottest content based on the number of times a link is being tweeted. TweetMixx uses OAuth for login and is currently in beta.
As mentioned on TechCrunch,
TweetMixx works by skimming through tweets and looking for links. The more times a given link appears on Twitter, the higher placement it gets on TweetMixx. Likewise, you can log-in using your Twitter credentials and receive a personalized hotlist of tweets based only on the Twitter users you follow.

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