That's not a knock on Iverson, one of the most remarkable athletes of my lifetime (most guys his size never sniff the NBA, much less average 27.7 points over 12 seasons).
It's just that the Nuggets got a player who is almost as good, fits their needs better and won't bolt to another team after this season.
The Nuggets have a potential big-time scorer in J.R. Smith, who happens to play shooting guard. Though Iverson is an effective ballhandler and passer, he's also most effective at shooting guard. The Nuggets had an inefficient glut of one type of resource.
With Billups, the Nuggets not only get a natural point guard, but they also clear minutes for Smith and give Carmelo Anthony (Towson Catholic) more operating space and shot opportunities.
The Iverson/Anthony pairing was hardly a failure. They scored a ton of points and led the Nuggets to the playoffs twice. But Denver couldn't get past the first round either time, and Iverson was set to become a free agent in the offseason. It was time to try something new.
Billups is a year younger, he's a better defender and he's a more natural complement to the team's best players. Remarkable as Iverson is, he's 33. He has played a ton of minutes, and his wiry body has taken an ungodly pounding. Maybe he can continue to defy nature, but the Nuggets made a smart bet in moving him when they did.