There are some things that are indisputable. Shooting with an OVF is a preferred method for most on this board, I'm pretty sure.
That being said, I have both a Fuji X100 and just before Christmas, got a Sony RX100.
I prefer by far the shooting experience of the X100. I like a solid camera, holding it to my eye, and generally shooting like a rangefinder.
*However*...
Since I got the RX100 I've picked up the Fuji twice. The RX100 is totally pocketable, has a zoom range that would normally require a lens the size of a coffee can on a dSLR, has about as many pixels as my 5DmkII, is faster than the X100 in both focus and shooting/storage, and generally has the same IQ. The only two things I don't prefer for a super-compact like the RX is that it doesn't have the 50mm wide-open bokeh for portraits (you can get some, but it's not effortless), and I don't prefer waving the camera at arms' length to shoot.
The Fuji X20 looks like a terrific camera, but if I require an OVF, the X100 is a much better shooter, both technically and comfort-wise.
If I don't need the OVF, well...the RX100 is a much better camera, period. I very often wonder why I still need the 5DmkII (yes, I said that).