About 1.2 million people are registered with House Party, and 900,000 of them actively send in emails hoping to sponsor a party, says CEO Michael Perry.
Being selected to host is as competitive as getting into a big-name college. "We might have 50,000 applicants to host 5,000 parties," Perry says. Those beating the odds earn high marks when House Party analyzes their "social currency" on Internet networking sites.
Another group sponsoring similar product fests is the parenting magazine Kiwi. About 16,000 "mom ambassadors" are registered and approved to host get-togethers. All must complete an application at GreenMomsMeet.com, "so we are sure they are really interested" in the program, says Sarah Smith, editorial director of May Media Group, Kiwi's parent in New York.