Does it have a 'snap focus' mode? Those things are point and shoot features
Snap focus is a very sane zone focus feature for autofocus cameras, especially those designed as go-everywhere cameras and particularly so for cameras that appeal to rangefinder users or wannabes. What type of camera user makes use of zone focus more these days than any other? Probably rangefinder shooters. More makers should rip this elegant zone focus idea off of Ricoh. As the X100 is an autofocus "rangefinder style" camera, the feature surely wouldn't be out of place on it.
But... you can work around this missing feature.
I had the X100 in manual focus mode most of the time, and used AFL to either spot focus and recompose, or used the AFL button to pre-focus at a specific distance(s) having memorized a few useful depth of field ranges for specific apertures. Snap focus would save a step and some memory work.
One problem (may have been addressed with firmware updates) was that the focus target in manual focus mode inexplicably grew much larger. Others have mentioned other AF quirks, some of which have been improved upon by new firmware.
Aperture dance, another quirk.
Occasional but too frequent camera crash/lockup if you move a control or try to operate the menu while the camera is writing an image to the SD card. Very quirky.
Horrible manual focus experience, a big quirk. I'm not saying the camera should act like a manual focus-only camera, but when AF doesn't do the job, MF must, and MF was very painful on this camera. This wouldn't have been so bad if the AF worked reliably in all situations but when you were in a situation where AF didn't work, MF would hardly come to the rescue. This has been improved to some degree by later firmware.
Another quirk which irked me was the single user definable function button and the useless RAW button which took Fujifilm EONS to finally release a firmware update that allowed users to redefine the useless RAW button.
As the minimum shutter speed is limited to 1/1000th at f/2, if shooting out of doors frequently many want to define the Fn button to toggle the ND filter. Back in the day Auto ISO was buried in another menu. If moving from indoors to outdoors and back frequently you could be in a situation where you'd frequently be menu diving because you couldn't assign frequently accessed menu items to more than one function button. Now you can do two, if I understand the changes correctly.
The quirky nature of the camera is well deserved IMO, as it took Fujifilm forever and a day to finally release the firmware for the camera that should have shipped with it on day one. Unfortunately the camera is now nearer the end of its life (X200 bound to come sometime soon) than the beginning. Better late than never?
I had a love hate relationship with my X100, but I do miss the silent shutter in a carry everywhere larger sensor camera, so much so that I've decided to get a RX1. No doubt it'll have quirks as well.