Are Western Buddhists generally older?

I was listening to the introductory podcast from the Buddhist Geeks series. The guys presenting are of the younger demographic i.e. in their twenties. They felt that this was unusual and most Western Buddhist practioners were older - baby boomer generation. Does anyone have any surveys or statistics that analyse self identified Buddhists in the West by age? Do they tend to be older? Or is the age range pretty much similar to the population at large?