I really hope his interest in Dallas and San Antonio is just a ploy to apply pressure to the Nets - for money, guarantees of who he'll be playing with, etc. This concern that he's voiced of his "legacy" is mind-numbing.
If he goes to San Antonio and wins a championship, his legacy will be that he rode Duncan's coattails. It's a similar situation with Dallas in that they're already a championship contender (as long as they don't have to play the Lakers).
If he goes to either San Antonio or Dallas and never wins a championship, then his legacy is that he's a loser.
He's on a young team that's only going to get better and that seems to have a ticket to the finals for the forseeable future. This means he can stay in NJ, and wait until his team is good enough to win one series over a Western Conference champion, and he's got his trophy. Or more than one trophy, as it doesn't look like the Eastern Conference will be a problem anytime soon. He's also the savior for this team. You can't beat the legacy of going from wife-beater to savior to champion.