Upcoming.org is popular among people who want to team up and synchronize their social calendars with others in their area. And it was the enthusiasm and involvement of Upcoming's community that sparked Yahoo!'s interest, according to Paul Levine, general manager of Yahoo! Local.

"We're not only after more of a presence in the event space," said Levine. "It's important to tap into the energy of a community as vibrant as Upcoming's is."

Apart from working with mobile company Nokia on various wireless services, Upcoming has developed a groups feature that allows people to organize and discuss familiar events and interests.

Rivals like Google, America Online, and Microsoft's MSN have all been building up their own local search abilities. For example, in May, Google bought Dodgeball.com, a small New York company that helps mobile-phone users organize meetings and other events with friends and associates.

Yahoo! already offers a robust Yahoo! Groups service, where netizens can congregate online--and it recently launched Yahoo! 360, which is the company's current answer to the social networking phenomena led by News Corp.'s MySpace.

Levine said Yahoo! will maintain Upcoming.org as a separate Web entity for now, rather than incorporate Upcoming's technology into either Yahoo! Groups or Yahoo! 360. He added that there were numerous possibilities, but none that he was prepared to speak about at the moment.

At present, Yahoo! plans to sell contextual advertising next to Upcoming's local event listings, an approach that is similar to the one Google takes with its own ads alongside local content.

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