Upload & Sell: On
In my own Leica experience, I find that my increasing comfort with a lack of "tack" sharpness in some (though not all) images arises from the fact that I am using very fast (f/1.4) primes wide open almost all the time. Often, very little is in focus anyway, and learning how to master these kinds of optical effects takes a long time. Moreover, it's hard to always nail focus with such shallow DoF, though it's amazing how much better one gets with practice.
That said, stop down just a little bit, and images can become stupidly sharp. Even at f/2 or f/2.8, nailing focus and obtaining ridiculously sharp images becomes much easier. At f/5.6 or slower, the Leica optics are so good that they will (almost) obviate the benefits of a higher resolution sensor, such as a Nikon D800. For example, in a recent studio shot that my wife and I did (some results of which are posted on this thread), we used both a Nikon D800 with a 24-70 f/2.8 at f/8, and the latest generation Leica 50 on an M240 at f/8. I was surprised to see that the sharpness and overall detail in the Leica shots was virtually indistinguishable from the Nikon images. I could not really see the differences between the files until looking past 400% magnification, and even then, the distinctions were incredibly subtle.