Kat thanks for asking this question. I'm going to be looking for a bike soon too (Just signed up for a Tri) and I was wondering about the weight issue too as I'm currently down to 213.

Does anyone know if some seats are better then others for heavier riders? Currently I have a dirt bike I'm using so it has one of those Um... Large seats with the springs in them which has been very comfortable but I'm not sure would work out with a road bike. Seat comfort has a lot to do with how long I'm able to ride.