What about swimming or gymnastics, madanthonywayne?
I'm quite into basketball myself (so forgive me if I make a long post), and in my opinion race doesn't have anything to do with it.
To begin with, basketball isn't 90% black. I think it is like 70%. I had heard 80% a few years ago but I'm thinking that has changed lately.
If you look at the white athletes that have succeeded it is enough to show that white people can compete on the same level in basketball. Why they don't is not because of ability. Larry Bird isn't a good example imo because he wasn't a great athlete (he had great endurance and toughness but not jumping ability and great speed). There are plenty of white athletes in the NBA who are great athletes though.
I would say the the traits needed for the NBA are:
1. Jumping ability, obviously.
2. Sprinting ability. Not only do you do a lot of sprints in the NBA but how well you sprint, along with your jumping ability, is a good measure of your all around explosiveness, so the first two translate into almost every other physical part of basketball.
3. Physical attributes. Height, wingspan, and hand size. Almost any height can play in the NBA but it limits position obviously. If you have below average wingspan and hand size you will have a lot of trouble.
White people have 1 and 2. I can vouch from personal experience that jumping ability is not something you are born with, it is something that you train (I dunk at 6'2 pretty well). Same for sprinting. Regarding sprinting it may be dominated by blacks at the olympic level but that is irrelevant when discussing the NBA (and a different issue that would require a bit of length so I'll avoid that).
Any race can train aspects 1 and 2 enough for the NBA level. As long as you aren't below 5'10 (there are a lot of 5'10 players but they get listed as 6'1 b/c they measure w/ shoes on) and don't have small hands and wingspan, the only thing keeping you out of the NBA is your desire.
Bear with me because I have a lot of other ways to make my case.
Take Kevin Durant, the best college player, #2 draft pick. A guy who just got a 60 million dollar shoe contract. He isn't a great athlete. He couldn't even bench press 185 lbs on the combine, he was the slowest sprinter and had a low jump. If he is in the NBA because of his race, it must mean that blacks are more intelligent, because he, along with many other black basketball players, are not great athletes.
So, why are there more black people in the NBA? That's easy, they play the game more, it is a bigger part of their culture. The average white guy's sports list is, much to my chagrin, the NFL, MLB, NHL, Nascar, Golf, Women's Tennis, and then the NBA. The average black guy's list has the NBA and the NFL at the top.
I go to a couple of basketball gyms where black people are probably about the national ratio in local population, yet at the gym, just like the NBA, blacks are the vast majority of the players. I see no reason to explain why they are in the NBA other than that they play the game far more.
I'm not to sure about this, but I've heard about quite a few NBA athletes who have been raised by their parents to play basketball. I've heard a lot of stories like this, but I don't know how common it is. It's like some parents are hoping their kid becomes some millionaire NBA player so they choose it for them.