Compact, the definition of, the same width and depth as Canon's tiny Digital IXUS (S100 ELPH) but taller (by 14 mm) and exactly the same weight (including batteries). The major differences? Well the 40i can play MP3's, the S100 has a zoom lens vs. the fixed lens of the 40i, the 40i has a 1.8" LCD vs. the S100's 1.5", the 40i has FujiFilm's 2.4 megapixel SuperCCD... Street prices of the two cameras should be similar (plus or minus $50).
Back to the design, the body has that strong metallic quality feel (magnesium alloy) with an automatic sliding metal lens cover. The squarish design is actually quite comfortable to hold, small and light enough to slip into a jacket pocket as an overall package the 40i has a portability and gadget factor that will attract many people...
Rear LCD Display
The rear LCD, although small is larger than that found on the Canon Digital IXUS (a comparable size digicam), Fujifilm had a little more height in the body and space to put the 1.8" LCD.
It has a good range (ten) of brightness levels (accessed by holding the DISP button for more than 4 seconds) and was on the whole relatively good for the size of camera.
As the 40i is so small, so is its viewfinder, almost like peering through the viewfinder of a disposable camera... The green light next to the viewfinder indicates power-on and camera "ready", when focusing it will blink and continuing blinking if it cannot get a good focus lock.
It's a criticism I level at most compact digital cameras and it's about time manufacturers started to consider putting better (read larger) viewfinders on their cameras(or better still mini-LCD TTL).
Battery / SmartMedia Compartment
The flash built into the 40i is smaller and not as powerful as that found in the 4700Z, this flash has an output rating of 0.4 - 2.5 m (1.3 - 8.2 ft) it should be fine for taking portraits but not quite enough for group shots...