With the lockout ending today, the owners felt the deal would go against what was agreed upon in the Collective Bargaining agreement. The trade likely would have made the Lakers a super team, while the Hornets, despite Odom and a few more players, and the Rockets with Gasol, would both likely be mediocre for years to come.
I personally feel the NBA did the right thing here, reasons being that there needs to be some sort of balance in the league. Like LeBron was the Cavaliers, and Chris Bosh was the Raptors, Chris Paul is the Hornets.
After LeBron and Bosh both left for Miami, their former teams floundered due to a loss of star power. Cleveland set the mark for futility with 26 consecutive losses, while Toronto could not stay out of the Atlantic cellar.
If Paul had been traded, despite Odom, it would be likely the Hornets would encounter the same problems as the Cavaliers and Raptors.
Behind Paul, there is no true leader. Trevor Ariza is decent, but he's not proven to be a leader, David West is also okay, but he's no Paul. The players the Hornets would receive in return would help the team, but they could only get them so far, much like what happened last year with the Denver Nuggets.
I'm not saying that Paul has to stay in New Orleans forever, but I think that if the NBA wants to push the new Collective Bargaining Agreement forward, especially if they want to enforce a competitive balance, then putting their foot down is the best idea.
I also understand that everybody wants to be a Laker, but the truth is, if all the good players wanted to be Lakers and got their wish, then the Lakers would continually have the advantage year after year. It's time to see someone other than Los Angeles make it deep in the playoffs, and it starts now.