I haven't played one yet, but I watched and listened to this video and came away thinking I like the sound of the J-35 better than the J-45. To my ears, it sounds a lot less muffled and let's not forget the big price difference. A no-brainer for me if I was in the market for one of 'em. I expect Gibson will sell all they can turn out. I haven't owned a Gibson since way back in the late '60s, but this new J-35 could change that.
http://www.youtube.com/watch?v=8ePmR2WMUMk