We were one of the first sites to break the news about the Fuji X100, the innovative rangefinder-esque compact with the hybrid viewfinder, APS-C sensor and attractive but fixed 35mm f/2 equivalent lens. Details at the time of the announcement were sketchy, though, as the X100 was and is still a work in progress. However, the company's dedicated X100 micro-site launched shortly after the news of the camera continues to add details, as and when they're finalized by Japan. If you're wondering what sort of expertise Fuji have then think of their now discontinued 6x7 and 6x9 rangefinders, and the Hasselblad XPan, which was made by...yep, you guessed it, Fuji.
Fuji's viewfinder design team, from left to right, Takashi Soga, Hitoshi Miyano and Shigeru Kondo, talk about the challenges of combining the optical and electronic components of the viewfinder, including a 0.5x magnification.
While there's an overlay of shooting data during capture (see below), the viewfinder will be able show the live-view and the captured image during playback, thanks to the viewfinder shutter mechanism (which will close-off the optical viewfinder).
The X100 has both an optical viewfinder, and an electronic viewfinder, which, by using a prism rather like that found in rangefinder cameras, can overlay data (exposure details, distance scale, histogram and WB) from the EVF into the optical path. The result is that the X-100 will have the contrast and clarity of an optical finder with the convenience of an EVF.
A shutter is required to close-off the optical viewfinder during playback and live-view. The X100 has a 1.44k dot resolution LCD in the viewfinder (detailed above). More details of the hybrid viewfinder can now be found here. And, be sure not to miss page two, it's easily over-looked.