If he can make it to 32 at the level he is playing now, it will have been a very good career for him. After that, he won't have anything left to give most likely. If Miami is smart, they finally get him an extra scorer (and I mean a legit scorer). They need to pair Bosh with him. And what they need to do is limit his minutes in games that they have substantial leads in (if they end up being a championship caliber team) so that he is fresh going into the playoffs each year and can elongate his career.
Totally right again, they need to trade Jermaine O'Neal away for a box of wrapping tape and a case of Gatorade and get the guy a legitimate scorer to compliment him.
Just don't see Wade or Kobe lasting that long in the perspective I was talking about. Doesn't matter what his age is. Anything can happen but Lebron, Durant, Anthony, etc... will be in the league many years after them IMO.