The S9600 had pretty brisk performance, so the new model has a lot to live up to. It starts up in just over 2.5 seconds, and shuts down again even faster, pretty good for a super-zoom camera. Shot-to-shot time in single shot mode and maximum JPEG quality mode is a very respectable one frame a second, while in long-period continuous mode it can manage an equally respectable 0.8 seconds per shot. The S100FS has multiple continuous capture modes, including several bracketing modes, all with different shooting rates, but in the fast top-seven mode it can manage over two frames a second.
The autofocus system is fast for a super-zoom camera, although I have seen faster, especially on DSLRs. In good light and wide-angle zoom settings it focuses in a fraction of a second, although it does slow down somewhat in lower light and at longer zoom settings. It is still impressively quick for a contrast-detection system though, on a par with the best of the competition.
In terms of picture quality, there's no question that the S100FS in an impressive camera. For overall detail and clarity it comes closer to DSLR quality than any other bridge camera I've tried, and colour depth and high-ISO noise control are also very good. The big SuperCCD HR produces virtually no noise at 800 ISO, and usable images even at 3200 ISO, although it has to be said that the 3-megapixel 10,000 ISO setting is a bit of a gimmick. The only fly in the ointment is the lens quality. At the widest angle setting it does produce a fair amount of barrel distortion, but a more serious problem is the very visible chromatic aberration around the edges of the frame. The advantage of an interchangeable lens DSLR is that you can always save up for a better quality lens, but with the S100FS you're stuck with it. It is possible to apply some correction in Photoshop when converting from RAW mode, but this is a patch at best. Fortunately the problem is far less noticeable at longer focal lengths.
So far then the S100FS is doing well, but there is one final point that has to be made, and it could be the decisive factor in the success or failure of the S100FS. Fujifilm is advertising the camera as an alternative to a digital SLR, claiming that it provides an "all-in-one solution for photo enthusiasts … seeking the manual controls and functionality of a DSLR without the bulk, hassle and expense of additional lenses..."
Now I don't mind a bit of marketing hyperbole, in fact I expect it, however while I am very impressed by the S100FS, it's not really fair or reasonable to compare it to an SLR. As a camera it stands head and shoulders above every other bridge camera on the market, but even an entry-level DSLR will beat it in every important respect, including performance, features and image quality. The size of the sensor, the contrast detection AF system and the quality of the lens are simply not up to the standard of even basic DSLR systems. This is really the S100FS's only weakness, because it is currently selling for around £390, while you can buy a Sony Alpha A200 with an 18-70mm lens for £299, or a Nikon D40 with both an 18-55mm and 55-200mm for £438. Frankly, if I was looking to spend nearly £400 on a camera, I'd get a proper DSLR. If the S100FS drops in price to the level that the S9600 is at currently then it will be a bargain of galactic proportions, but right at the moment it's simply too expensive to compete.
The Fujifilm S100FS is a worthy successor to the S9600, and has superior handling, performance and image quality to any other super-zoom camera on the market, but comparing it to a real DSLR is a bit disingenuous. It is very expensive, more expensive even than an entry-level DSLR, and for all its qualities it doesn't quite compete on the same level.