I have carbon seatposts on both of my road bikes and I have not had any problems with them so far. My oldest would be coming up to 3 years of age.

Just remember that if you decide to buy anything that clips onto the seatpost read carefully if it can be mounted to carbon. I got myself a lovely hightail bag from Terry Bicycles for overnight trips on the bike but it can not be used with carbon. So I have an aluminium seatpost that I use for those rides.