My bikes are for Going Places and Doing Things. A kickstand come in handy, so I have them on both bikes. If, however, I were to race I'd be looking to save every scrap of weight possible. No kickstand.

It all depends on the bike, and the intended uses. The biggest issue is if the kickstand (bell, flag, bucket panniers, etc.) make YOU smile. It IS your bike, after all.

That said, I like the folding stands, I'd be good with one.