Me, obviously

.
With Sony alpha-mount bodies and lenses, I have all my needs covered, except two:
• high-quality files recorded in low-light, and
• a silent, inconspicuous (or socially non-interupting) camera.
The RX1 is a near perfect complement to what I already own.
If I could get the first (high quality in low-light) in all my Sony bodies for the same price, I might do it. But that still leaves me with nothing easily-carried and inconspicuously-used.
If I could get the second (inconspicuousness) in all my Sony bodies for the same price, I wouldn't do it. First, my a-mount lenses are too big to achieve this. Second, I would rather spend my money on being able to record high IQ files in low light.
I have quibbles with the RX1 design -- for me, the lack of an articulating LCD is first, followed by all the others mentioned by reviewers including our esteemed Michael -- but they are secondary to its primary qualities (high IQ files, exceptional low-light recording, silent & inconspicuous) and are not flaws fatal to my decision to purchase.
Me aside, I think Michael has twice put it very well in this thread (and much more succinctly than I would be allowed):
{It is} a world-class instrument for a wide range of types of photography
{I}t combines a fast high quality lens, a great sensor and is small enough so that no one will confuse me with the official photographer. :-)