The M9 is almost perfect, save the (over) price of the body and lenses. I've had a raft of M cameras, the M6 being the best of the bunch. What I eventually realized is that the Fuji X100 suits me just fine, and the extra features, which I never thought I'd use, are really welcome. It has roughly 90% of the IQ of an M8, but with a (much) broader DR, and quality ISO up to, really, 3200 with a bit of work. The in camera JPEGS are really very good, as is the color and auto WB. Really amazing. I've never used JPEGS straight from the camera, but the little Fuji makes that possible. I use the Fuji just like I used my M8 and M9: as B camera on editorial shoots and for street shooting, as well as shots of the kids etc.
The problem with Leica, in my mind, is that the cameras and lenses are too expensive for their limited usability in either a professional or personal context. They are ideal for street shooting and any situation where their small size and low key presence is needed, but other cameras can do this as well, for far less capital. And in a JPEG digital world, the M9 files are overkill in most situations.
The major technical issue, to me, are the fixed, inaccurate framelines. I'm sure this was an issue with the film cameras, but with digital and instant review, the issue is immediatly brought to your attention, causing you to reshoot and reshoot and reshoot until what you saw through teh VF shows up on the screen. I think I never noticed this with film because the lag time between pressing the buton and seeing the contacts made fuzzy the memory of what you were trying to shoot. Otherwise, the VF of the M cameras is fine with me.
I hope they keep making them, and I hope they don't fool around too much with the VF. Maybe make the frame lines truly variable, and cut the cost of them to something that a professional would really use, not just a novelty or fetish item.