Any young man with a first round draft promise should watch this video before making his decision. The rule that disallows HS players from declaring for the NBA draft is unfair to players and fans.
If a young man wants to earn a living right away as a basketball player he has that right. Unfortunately the NBAPA didn't feel strongly enough about the issue to fight for that in their last labor agreement. Too bad all the HS-to-pros in the union, like KG, Kobe, and LBJ, didn't fight for it. I know Jermaine O'Neal was outspoken in his belief that the new rule was unfair and bad for the game. As an NBA fan, I enjoyed watching LeBron, Shaq, KG, and Kobe as rookies, and I even enjoyed watching some of the HS guys who struggled their first year in the league. HS-to-pros guys are generally more successful long term than players who go the college route (probably because they're more talented than the average college prospect).
One and done does nothing but delay the inevitable, anyways. And in the worse case scenario, a catastrophic injury may take away a talented young man's future, like what might have happened to Noel. Without the new rule, he's be on an NBA roster right now, with at least $5m guaranteed to him, rehabbing his injury with the best resources that money can buy.