I just joined the Brooks crowd. My reasoning was a) I'm tired of having to buy a new saddle every few years, b) the wonderful English 3 speeds that my school cycling club had were so equipped, and c) just as real cars have tonneau covers, real bikes have saddles with a spring in back.
It is one of the pre-aged ones, and very comfortable right out of the box. In all fairness, the two year old saddle it replaced was missing much of its cover and some of its foam, so almost anything would have felt better. However, the Brooks just feels right, so put me in the pro-Brooks column.
My one fear is that I would not be able to wear light colored pants with the thing, but this has proven unfounded - a good thing, too, because summer in the DC area is no place for dark pants.