Well, I'll pipe up and be contrarian. I am perfectly happy there is no advance lever on the M9. Yes, I like shooting film and I love my MP, BUT the advantage the M9 has is that you can keep shooting without taking the camera away from your eye.
As I've said before, I shoot a lot of live concert work. Back when I was much younger (alas) and shooting film SLRs, I had a motor drive on every camera. Mind you, I didn't machine-gun with them (put them all n single shot mode only), but with the motor drives on, I didn't have to take my eye away from the camera, cock the film advance for the next shoot, and lose a great moment.
I had a motor drive for the M6 I had many years ago, but I got rid of it pretty quick. It was big and clumsy,and when attached to the camera, the whole assembly seemed as big as a dinner plate--and was hard to handle. One of the things I liked about the Konica Hexar RF I had was its built-in motor drive, in a camera the same size as a Leica M. I used to wonder why Leica couldn't do that...
So if you want a digi-M with "back to the past" film-M characteristics, fine. But frankly, I'd rather not revel in the glories of a film-style "advance lever." I'd rather keep the camera glued to my eye so I don't miss that Really Great Shot, thank you....