RacerX,
I don't disagree and you do point out good exceptions to the rules that define who is good at what. I tend to think though, that if you look at local racers and lower cat. guys the rule tends to hold up. Thin guys, narrow hips tend to be climbers. Bigger stronger guys with thighs like tree trunks tend to sprint.
I think that a new guy can get a decent idea of what he might do well by looking at body type. I know that as I watched Euro races I figured that I would be a climber more than a sprinter. Even now, at 30, I weight under 140 at 5'10". You're right though, that riding with others will reinforce your view or change it all together. I did find that I go up hills a little faster than many others.
And I have made exactly $0 to show for it!