There are only two movements within Christianity that are attracting young people ages 18-35. One is the new Reformed movement (kind of a younger, hipper Evangelical Calvinism) and the other is the Emerging Church movement with its most liberal wing led by an organization known as The Emergent Village. Check out the following links to learn about it. The first is the obligatory Wikipedia article and the second is a talk given by pastor Mark Driscoll of Mars Hill Church in Seattle. Driscoll is part of the New Reformed Movement but was a leader of the "emerging church" at one time (at one point, I considered myself part of it as well but we have both since repented). Oh, and as far as my thoughts on Emergent...be afraid...be very afraid.
http://en.wikipedia.org/wiki/Emerging_Church
http://www.sebts.edu/chapel/chapelMessages.cfm?filter_sortdirection=DESC&filter_semesterid=0&Page=3