I like how he's developed a nice jumper over the past year. His defense is still above average and he is a worthwhile prospect. I would comfortably value him at 5-8 million per year.
I was looking at teams with cap space and noticed the Bobcats could have quite a bit if they renounced players. But then I look at Henderson and ask why they'd want to renounce him... He'd be hard to replace.