I hate sounding like a fanboy, but I must say that the Sony RX1 presses all the right buttons for me – no pun intended. Build quality is exemplary, haptics are mostly excellent, as are control placement and customizability. The Zeiss lens is truly excellent, and having a full-frame 24MP camera that can fit in a coat pocket and go almost anywhere without being an encumbrance makes this camera greatly appealing. One can always find quibbles in any piece of equipment, but the RX1 is more operationally all-of-a-piece and desirable than just about any recent camera in my experience.
Of course there's the issue of price, but frankly it's hard to imagine a camera being as well made with as terrific a lens for much less money. Quality costs.
The only competitor on the horizon that I can see is the forthcoming new Leica M, due late winter or early spring 2013. It too will be full frame, 24 Megapixel and have an accessory EVF. Of course it will be quite a bit larger, heavier, and much more expensive even without a lens, but the comparisons will be inevitable and as a long-time Leica aficionado I'll be among the first to do them.
In the meantime, unlike most cameras that cross my desk, the Sony RX1 has captured my attention and admiration. Indeed I bought one as soon as I could because it's just the ticket for the kind of travel and documentary shooting that I so much enjoy doing.