One thing that's pretty nice(and not commented) is that the M can become a complete camera. No need for external viewfinders for ultra wide and the possibility of close up photos, without, losing the ergonomics and experience of a coupled rangefinder. It lacks aperture indexing, of any kind, though, so metering is made at shooting aperture, bad for manual focusing through the lens.
Video is less likely to be used, given that other brands offer better alternatives(including true video cameras), without the big money. Also for video, the camera is just the begging of the investment.
The Leica ME I think is good for those who won't use Leica glass. You get 2 or 3 voigtlander lenses for $1500. The M9-P is the M9 without the red dot, so Leica already relaunched it's products once. Pointless IMHO, but many people even "upgraded" the camera, so I expect anything, from no sales to record ones.
I think I'll try to get a Fuji in the future. It's ergonomics is what I really want, big speed dial, and aperture on the lens, no need to look at the screen to set the desired config. I'll only miss the nice and easy manual focusing.
Full Frame to me is overrated. There's no true diference for normal use. Super high ISO speeds are only for specific very specific applications.
To me Voigtlander or Zeiss could launch coupled rangefinder with a APS-C sized sensor, and digital dedicated lenses for 28mm(equivalent) and bellow. That way problems related to wide angle in digital sensor can be circumvented with specific lens design, such a small retro focus. This way, we'd get everything, at affordable price, thinner body, with all the possibilities of this new "M", without any of the problems related to the big sensor.