I'm just wasting time here (only because I can't get on the road yet ...). It has occurred to me, that depending on what part of the country you are in, you will most likely see a different distribution of bikes on the road.
For example, I live in northern california, but do visit family in southern california quite often. I have noticed that in northern california, I see plenty of Calfees, and in southern california, I see plenty of Giant OCR's and a good number of Serottas.
It would be interesting to see what the distribution is of various bikes, based on geography. But then again, part of it may depend on racing team loyalties, and whether or not your ride for recreation, or for racing!!!