Congratulations on your new M10M. Enjoy it in good health!Got my M10M on Monday and had a brief chance to shoot with it on Tuesday. So far, so good- I have uploaded some full-res JPEGs (converted from DNG in Lightroom) here- https://adobe.ly/38Rs4xy . The ISO 6400 shots were pushed about a half stop in post- it's definitely cleaner than the M246 at high ISO, but not enough that I'd say that it really increases the shooting envelope (so far).
The sensor seems to hold highlights better than the one in the M 246- I had read that a lot of people shoot 0.7 EV under metered exposure on the M 246 to preserve highlights, and I found myself doing the same. This doesn't seem as necessary on the M10M.
Otherwise, it does what it says on the tin- it's a monochrome M10. If you like the M10, and like Monochrome, and have the means, it's wonderful. Everything that made the M 246 great is here, and the whole package is a bit more compact, quicker, and nicer to use.
One surprising bone to pick- the Leica FOTOS app. I never bothered to get it for my regular M10, but part of the beauty of monochrome files is that there's less processing required- perfect for quickie mobile edits. On top of a camera body that just cost me over $9k (inclusive of tax in NY State), Leica has the temerity to make a $50/year subscription ("Leica FOTOS Pro") basically essential to use WiFi with the camera. If I understand correctly, you can't transfer full-sized DNGs over WiFi without paying for the Pro subscription, and also don't have even basic integration with Lightroom Mobile (that is, "Open in Lightroom Mobile") without ponying up the 50 bucks. This is pretty insulting- literally every other camera company I can think of offers this functionality as part of the standard offering. I've already signed up for the subscription, because usable WiFi is a new feature (vs. the old 246) I was actually eager to use. I couldn't imagine any other camera maker pulling this without being completely savaged in the reviews.
The free version of FOTOS allows transferring full-sized DNGs to the phone (tried it with success).
The subscription gives you a direct (vs indirect) transfer of files to Lightroom and the iPad version of the app. I do not find any need for the subscription of FOTOS. Looking forward to the app update that implements proper GPS tagging.