The 2007 holiday selling season likely will be remembered as the year social marketing hit the mainstream. A Oneupweb study of the 12 hottest products for the upcoming holiday season shows a remarkably creative variety of social media strategies and tactics being employed by savvy online marketers as they successfully generate advanced buzz and ensuing engagement. For the multichannel marketer who has yet to adopt a specific social-marketing strategy, it may appear a daunting, if not impossible, task to jump into during this holiday selling season. But here are four social tactics you might want to consider. 1. Participate in existing social networks.