What I've found to be our biggest benefit from competitive gymnastics is that it has given my girls the confidence that if they set their minds to do something, they can figure out how to do it. It might take a scraped knee and a failure or too, but when they "get" it, they've made it! That's a really important life skill for a kid to learn at such a young age.
Also, I guess I look at gymnastics as a marathon, not a sprint. They might get tired or lag behind or take a different route down the line, but in doing so they will have the foundation of hardwork, discipline, looking at both the whole and the parts, and solid conditioning to help them achieve any future goals.
Do I think my girls will end up in the Olympics or even on a college team? Probably not. But, do I think they will still be amazing, well-round, and successful? Definitely.
I feel the same way about any sport or activity. My boys are competitive swimmers (and divers....gulp, I still panic at that thought--they're tiny) and they work HARD to be their best. But, in my opinion, they are gaining just as much if not more than what they would if they played six or seven different sports at just the recreational level.
Side note--gymnastics is GREAT conditioning for hundreds of other sports. Did anyone catch the Olympics puff piece about Johnny Weir and Evan Lysacek's training regimes? Definitely some gymnastics there.
Whew, sorry I was so long winded. I'm horridly verbose