Facebook Evolution

The most common response I get from my 35 - 45 year old peer group when sending an invitation to Facebook is "are you 16?".....then they try it, and it works, and they are connecting to many old friends who also like it, although they to first ask they question is "are you 16?". It will be interesting to see how this reluctant receptivity becomes more viral to the midlife crowd, and what impact their revenue model will have if the age skus higher and how quickly a newer/hipper social network evolves for the teen/20s crowd...............