I decided not to buy an M9 after reading all the anxiety about the sensor problem. I would be fine with one that had had its sensor replaced, if it meant that there should be no more problems. But evidently that is not the case, if the replacement is the same as the one that failed.
I do have an M8.2. For a while I thought I might upgrade to the M9, but now I'm glad to keep the M8.2, which is apparently less trouble-prone (if not trouble-free).
Actually, I think the M8.2 is a better camera for me, anyway. The finder frames are more accurate at my usual shooting distances. I can use my 28mm lens on it, and I can see the 28mm framelines (37mm equivalent) with my glasses on. If I tried to use my 28mm on an M9, I wouldn't be able to see the full-size 28mm framelines. And I can get the 28mm FOV by using my 21mm lens and a 28mm auxiliary finder.
Then again, I wish my M8.2 let me enter the focal length manually, as I've been resisting paying to have my lenses coded. And they are up to what, now, $300 for this? And my M-coder doesn't work too well on many lenses. The 28mm Summicron takes the coding very well, but that's an exception. The 21mm tends to read out wrong when coded. My 15mm CV reads out as 18mm. And my 35mm version IV can't be coded at all, there's a screw in the way.
I like my D700 better. No frustrations at all. Same goes for the X-100, X-10, D-Lux 6.