This is no in-depth review of the three cameras, just a quick image quality comparison. The pics speak for themselves, actually. What it basically shows is the X10 is a great entry-level compact camera, which provides nice results if you don't crop too much. The X100 actually holds up pretty well against the X-Pro1.
All shots were done with the same settings, in JPEG mode, no filters, no post-processing. Please note that I had a hard time getting as bright a shot from the X10 than with its bigger brothers, I can't say that I understand why.