Tweetbeat, from Kosmix
Headquarters: Mountain View, Calif.
Raised: $55 million
Twitter now has 90 million tweets per day flying through the site. How do you sort the important ones from the noise?
Enter Tweetbeat. Launched Wednesday, the site monitors Twitter to spotlight the top trending stories. Contextual data-mining technology highlights the most important tweets, including those from influential Twitterati and first-hand participants. "Tweetbeat doesn't show you every tweet about an event -- only the most meaningful ones," says co-founder Anand Rajaraman. The site is one of a handful Twitter has granted direct access to its real-time "firehose" of tweet data.
Tweetbeat drew more than 1 million visitors to a pilot test it ran during the World Cup. The site is ideal for high-profile events like an Apple keynote or a TV series finale, when thousands of users chime in at once on a topic. A graph tracks tweet volume along a timeline, and a reply feature lets users "rewind" and view tweaks at and around pivotal moments. Rajaraman showed the graph technology off using the tweetstream from TechCrunch Disrupt: "That spike that you see is the exact moment that the deal was signed onstage," he said, referring to AOL's acquisition of TechCrunch on Tuesday. "You can go to that exact moment to see the reactions."