Seattlepi.com reports that on October 8, about 20 students from the University of Washington were granted a sneak preview at a local watering hole of a new social networking service from a Seattle startup named Ripl. The event was one of several events that Ripl has sponsored in recent weeks, which serve not only as a method of generating buzz for the service, but also as a means of soliciting valuable feedback for the service’s target audience. This isn’t the only startup company attempting to tap into the demographic. Blue Dot recruited about 50 members of a Christian organization from UW to test its new service. Over pizza and soft drinks, these students offered feedback that has helped shape future versions of the service…