Have used mine now for over a year. Because of its size and the quality of its pictures, I now use it in preference to my Nikon D3000 kit. Like other reviewers, I agree that it is simple to use, takes beautifully crisp pictures, is built solidly (as are all Leicas) and is quite stylish. (But which came first, this Leica or its Panasonic Lumix equivalent, which is almost identical, has a Leica lens and is much, much cheaper?)
Pluses: all the above, and something that hasn't been mentioned: colours are reproduced wonderfully by the lens system on this camera, especially saturated colours (autumn light, sky, etc.)
Minuses: no viewfinder. OK, I know that they are becoming rarer on compact digital cameras, but having to focus through the LCD display, however clear, is a pain and causes more camera shake and discarded shots than I am happy with. With a camera capable of producing such beautiful images, this is disappointing.
Then there is the price. Is it worth it? For me, yes, because of the quality of the images, the robustness of the build (I owned a Lumix equivalent, and it hasn't lasted as well) and, let's face it, the Leica brand. But for many of you reading this, you might think that you could do a lot better with a high quality, high spec, digital compact from a Panasonic, Sony, Fuji or the like and even a Nikon or similar D/SLR kit, including another zoom lens. I think, as with all Leicas, price is going to be a valid concern.
More money than sense? Maybe.