Nata- I think most people here realize that the NBA Merchandise revenue is split among all teams. I also think that the NBA looks at this is the aggregate, meaning that while MJ may only see a portion, it would grow total revenues. The Bobcats are again ranked dead last in the NBA in merchandise revenue, so the new colors, new logo, new jerseys, etc haven't moved the needle very much.
I also think that your wrong on the $3m to "buy" the name, everything I've read has said it would cost $3M to rebrand so that includes redesign of logos, signage, etc.
As far as when to rebrand, I think the time is now, this subject has been a consistent topic and distraction from the 1st day he owned the team. It's time to put this subject to rest definitively and move on.
No matter what the team decides- this needs to be the final decision and it needs to come quickly.
As to your last question - if the team rebrands and still it's a ghost town, I think we have to look out for the vultures from other cities in a few years.