Well in my opinion Aspergers seems like a bit of a catchall diagnosis that doesn't really have much real scientific merit. I have NVLD, for example, and it's by most people diagnosed as Aspergers, but by a neuropsych, it's NLD. So "Aspergers" seems like a bit of a vague silly label psychs apply to people.
Anyway, though, I can halfway relate. I'm actually naturally very outgoing, as a kid, me randomly going up to adults and asking a million questions was cute, but as an adult, it apparently is not. As far as socializing, it depends, I'm weird in that going to say, a carnival wouldn't bother me much at all, and I find social situations like that easy, and am almost extroverted in that I feel a bit energized and not drained by them. My problems come mostly in small groups of friends of friends, clubs, etc.
I find it very easy to make friends, and people seem almost to naturally wanna talk to me. I can make a good first impression with someone, but once they get to know me, my "Aspie" qualities, whether it's social awkwardness about body language/eye contact, interests, or simply being "weird" shine through. As far as popular people, initially I got along well with them in school, I smile a lot, seem happy, quite outgoing, etc, but then they realize something is amiss, and yeah...
As far as athlete, it depends on the sport. Individual sports I do OK at, but team...no.
I'd say the test will come in the next few years, at your age I wasn't diagnosed. If you get yourself rejected alot socially, you may join the camp of nihilistic anti-social Aspies, but if you're lucky and manage to not stick out in a bad way, you'll look at your diagnosis and totally not care.