VIA Dan Carr Photo. A nice listing of the differences of the x10 versus the x100.
I think that serious professional photographers who want a travel friendly camera will much prefer the X100 over the X10. Someone who shoots photos for a living will also appreciate the limitations of a fixed 24mm lens and know how to use this to their advantage whereas consumers who are used to point and shoots with a large zoom factor will look upon the fixed lens as a weakness. There’s no getting around the high price of the X10 though for a camera that is essentially a point and shoot. Whilst they have included a few nice features, like manual zoom and 2/3″ sensor, it’s still going to go head to head with the Nikon P7100 which contains the same amount of controls for $100 less. This certainly puts the X10 in the premium lineup so if you are budget conscious then I feel there are better options out there.
I have been thinking about a x100 for a bit now and it all seems to boil down to sensor size.