Canon has faced much the same problem upgrading the S90 as Panasonic faced with the LX3; when a camera is that good there isn't much you can do to make it better.
The body of the camera is virtually identical in size and shape to the S90 but there are a few subtle changes. It is very solidly made with metal front and back, and the bottom panel is now also metal, with a metal tripod bush in the ideal position below the centre line of the lens. Only the top panel is made of plastic. There are only a few few external differences; the position of the on/off button and the ring function button on the top plate have been swapped, there is now a single larger hatch covering the ports on the right-hand side, and it now has two strap lugs, one on either end. The rear panel also carries a few alterations; the small thumb rest below the mode dial has been reduced to a mere nub, and the monitor screen has lost its raised surround and now sits flush with the body. Despite the plain shape, or perhaps because of it, the S95 is actually very comfortable to handle and the matt surface is easy to grip.
The monitor screen is the same size and resolution as the previous model, but is slightly improved with better brightness, contrast and colour reproduction. It has a very wide angle of view, and has a toughened glass screen with and anti-glare surface. Most of the S95's other external features are the same as the S90. The rear panel controls are large and well labelled, and thankfully the rotary bezel control around the D-pad has been improved. It is now stiffer and has a distinct “click2 as it turns, making it less likely to be accidentally jogged while shooting.
The S95 retains the unusual control ring around the lens barrel, which can be set to control any one of a number of parameters, including manual focus, zoom control, ISO, white balance, exposure compensation and more. It's a control that takes some getting used to, but the on-screen display when making adjustments makes it clear and easy to control.
Internally as well the S95 shares most of the earlier model's features, but with some improvements. Like the S90 it shares its sensor and processor with the latest G-series model, a 10.0-megapixel 1/1.7-inch CCD sensor and DIGIC 4, however Canon claims that the operation of these has been improved to enhance low-light performance and reduce noise.
A major addition to the S95's repertoire, and one area in which is scores over the LX5, is 1280 x 720 resolution, 24fps HD video with stereo audio, although optical zoom is not available while recording. Video is recorded in MOV H.264 format, with PCM linear audio. The video quality is good as long as digital zoom isn't used, and the audio quality too is pretty decent, with good stereo separation from two microphones mounted just below the lens.
Other new features include a very effective subject-tracking AF system, and the addition of in-camera HRD recording, useful for high-contrast or back-lit subjects. Dynamic range is also improved by the i-Contrast DR booster, which improves shadow detail without significantly increasing image noise.