Houston had a shot before they gave away Ariza. They made life a lot more difficult on themselves with that trade. Still have a decent shot at it though.
I think the Lakers will have stronger competition this season than in either of the past two seasons.
I agree that Portland has a very good chance, if they get some luck with injuries. If Greg Oden and Brandon Roy stay healthy, then they will be very hard to beat, but if either of those guys go down, then they are just another team.
I think the Rockets are in a similar situation. If Yao can stay healthy, they will be VERY good, but if not, they are not a real contender. I also have no problem with the Ariza trade. Since he should be the 6th man anyways behind Battier and Martin, I actually like Lee a little bit better for that role. Ariza is a guy with a lot of talent, but he doesn't seem to understand how to use it in the most efficient way, which is not good as a 6th man for a team like that.
I also think Dallas could be very good. I think Chandler is going to be great this year, and he gives them the deepest (with quality) front court this side of Boston. And having the entire season to integrate Butler into the offense should really help. And of course they still have some very tradable contracts, should the right trade present itself.