Pros excellent low-light performance, high speed shutter (40fps burst),
stereo mic, wide angle lens, mechanical stabilization combined w HS shutter to reduce blur, long battery life, slow motion video, optional RAW format, HD video, mini-HDMI output.
Cons While shooting video, optical zoom is disabled (though you can still use digital zoom.
Summary The Casio Exilim EX-FH100's four main draws over other cameras are it's low-light capability, its high speed burst photography, it's slow motion video, and it's loooong battery life.
The excellent low-light performance comes (mostly) from the back-illuminated CMOS sensor which allows for more light gathering than traditional sensors. The camera takes a better shot in low-light situations than similarly sized cameras (small sensor cameras) without the backlit sensor (Sony however has a similar sensor called EXMOR on some of its newest models).
The high speed features include both a high speed shutter that allows amazing action shots (30 shots at a rate of 40fps in burst mode), and high speed video filming for gorgeous slow-motion video (can slow 1 second down to 14 seconds at the max setting of 1,000fps).
The camera further leverages the above features for some neat tricks in difficult lighting situations, which are unusual abilities for this compact form-factor. The sensor and high speed shutter are used together for several preset modes that help in low light. "Lighting Mode" is suggested for situations where parts of the frame are bright and other parts are dim -- it takes several high speed shots at various settings, then combines them for a more evenly lit image. There's a similar mode for night shots. The combination helps keep noise unnoticable even at high ISOs.
The stereo mic is a nice plus over most other cameras (though also present on the only current competitor to this product, Sony's Cyber Shot DSC-HX5V). Other notable features are the wide angle lens, and the availability of a mode that combines mechanical image stabilization with the continuous shutter mode to reduce blur. There are also modes that use the continuous shutter to record both before and after the shutter is fully depressed, to allow you to choose a different moment if for example the person you are photographing closes thier eyes or changes thier expression.
Spec for spec, The Casio Exilim EX-FH100 and Sony's Cyber Shot DSC-HX5V are nearly identical. However, the Casio has a few advantages - a larger aperture, longer battery life (520 shots vs. 310 shots), a faster continuous shutter mode (40fps vs. 10 fps), slow motion video, the option of RAW format (useful if you like to manipulate images with professional photo tools), and priority modes (aperture, shutter - which are common but Sony omits them on the HX5V). On the other hand, the Sony allows use of the optical zoom while filming video (in movie mode the Casio only does digital zoom), has a panorama stitching mode, and has GPS capabilities with position & direction metadata.
While the basic functions are easy to use - even switching from HD video to slow motion is just a toggle switch -- I suggest reading the full manual on the accompanying CD. Certain things are not obvious, such as how to find the two particular video modes that allows switching on-the-fly from HD video to VGA slow-motion video (you don't use the Regular vs. HS video toggle switch for this because doing so stops the recording. For a seemless transition, you actually set the toggle switch to HS mode, and then choose a setting in the menu for on-the-fly transitions, which are then operated via the left & right keys).
Thankfully, Casio has eliminated the pointless video length limit they had put on the previous model, the FH10.
Note that while 30fps video can be up to 720p HD, and slow-motion video at 120fps is VGA quality, increasing the slow-motion beyond this (max is 1,000fps) results in decreasing the screen area displayed as a trade-off to maintain video quality at that data transfer rate. Worth mentioning here is that video can be output via the mini-HDMI out port. A composite A/V cable is included, but if you want mini-HDMI to regular HDMI, you'll have to buy your own cable.
For still shots in continuous shutter mode, it will take 30 shots (or fewer if you release the shutter button) at a rate that is selectable from a scale of 1fps over the duration of 30s, up to 40fps within 1s (yes, you are limited to 30 shots, but the rate goes up to 40fps).
I suggest you set the image quality to Fine and up the sharpness to +2 if you're going to be cropping or printing to large sizes. You'll also want to use a SDHC card that is rated "Class 6" or higher to ensure the memory can achieve the necessary sustained write rate to record HD video or high speed shots.