Here's an interesting way to look at being a contender. Look at them now. Lakers, Hornets, Jazz, San Antonio, Boston, Cleveland are have two things in common: 1) They top player is a dominant player that can put his team on their back and win a game, most in multiple ways and 2) they drafted that player. Kobe, CP3, Deron Williams, Duncan, Pierce (KG is not that type of player IMO) and James. Very few teams trade that that kind of player or dont have that kind of player - aka Detroit. You trade for the rest of the team maybe, but you need that 1 player. As good as Dirk is, he is NOT that kind of player. I think he's very talented obviously and if he's a second option, he'd be one of the best 1-2 punches in the game, but not at the level of the others.
And those players have a much better supporting cast except James. I'm not going to argue that Dirk is a top5 player b/c he's not, but I would say with a legit allstar 2nd option (and no JHo is not an allstar) like the rest of the players you mentioned, he is perfectly fine as the first option.
I don't see Dirk here much longer. Mavs aren't a threat and he has already stated even though he is committed to Dallas, he is open to exploring the market or retiring earlier than expected. I wouldn't say he has declined yet or will decline very much in 2010...the last half of last season, he was playing at a high level as he ever had. But who knows, I think the Mavs need to move in a different direction and completely rebuild if this season is indeed another wasted one.