I think it's a really bad idea to underestimate Houston - especially the way they have played the Spurs. And now that Denver has shed some of the egos and crazies, they are playing team basketball - that's always dangerous. If the Spurs reach the WCF, they will be over-achieving. No matter who they go through. Not saying they can't, just that they will be over-achieving.
There's a really good chance that injuries are going to play a big part in whoever reaches the WCF. I just hope that doesn't inlude the Spurs.