Top dials
Fujifilm embedded the ISO sensitivity dial inside the shutter-speed dial; to change ISO, you lift and turn.
Lens
The X100F has the same lens the first X100 had many years ago. It's a 23mm f2; with the X100F's APS-C sensor, it has the equivalent angle of view to a 35mm on a full-frame.
Exposure compensation
There's now a "C" mode on the exposure compensation dial that allows you to access a broader range of adjustments -- up to +/-5 EV -- via one of the jog dials.
Leverage
The lever switches the viewfinder between an EVF and an OVF with an electronic overlay.
Aperture ring
The X100 series has long had a manual aperture ring; now it supports 1/3 stop settings. While they're not labeled, they click in as you rotate.
Fn button
Since Fujifilm did away with the buttons down the left side of the camera back, now you access metering -- which the company refers to as "photometry" -- via the reprogrammable Fn button.
Could use a little more grip
While you can hold it and shoot single-handed, it's not as comfortable as I'd like.
Back
The back is much more streamlined than the previous model, with fewer buttons.
LCD
It's a little bigger and higher-resolution.