Leica used to have a M called the M-D many years ago and this week the name started to make the rounds again on the rumour sites. The rumours are contradictory. Some say it will be a Leica like the Leica M60 limited edition which is an M 240 but is missing the rear LCD.
That will appeal to some but I prefer the Panasonic GX8 and Epson RD solution to those who do not want a rear screen. They both have reversible and foldable rear screen, so you can either have the LCD or fold it over and have a plain leather back.
But there is a second rumour going around that is much more interesting, and that is that this Leica M-D is going to be a Leica that has no rangefinder but takes M glass, instead of the optical viewfinder it will have an EVF. Now that would appeal to many photographers.