Are you talking about the new carbon framed OCR? if you are, I had a quick look at one in my LBS last week. It seems to be less race focused than the TCR carbon and the LBS thought it would be popular for weekend road riders - the cafe set. The geometry seems quite a bit more relaxed. Nice looking bike however.
If you are talking of the Al framed OCR, no idea.
However, a local A grade rider has had an Al framed OCR and it has not held him back at all. Makes me think the real difference is not the bike but the rider - it's not about the bike! Go racing on your OCR - it will be better than some bikes you are racing against and not as good as others, but racing is more about tactics and fitness than bike snobbery. People on euro exotica will still look down on you because you are riding a Giant (I know - I have a TCR carbon, and I think it great). the best answer is to beat them!