Canon has changed the look of the PowerShot S2 IS with the new S3 IS, but not much. The newer model integrates a 6-megapixel CCD instead of 5 megapixels, and Canon has added a few new features, but ultimately, it's the same camera. That's not a bad thing -- the S2 remains a great camera, and the S3 carries on the tradition.
The Canon PowerShot S3 IS's aesthetic seems to be a cross between those of a classic VW Beetle and a Fisher-Price toy. Granted, it's the same body as its predecessor's, but the silver bits stand out more against the current version's iridescent, dark grey plastic than they did against the previous model's silver colouring. As with the S2, there's certainly enough here to keep you busy for a long time, though, and loving every minute of it. (For more details about the S2/S3's basic design and features, read our PowerShot S2 IS review.)
For the S3, Canon has upped the size of the flip-and-twist LCD to 51mm (2 inches) from 46mm, but it's still disappointingly small. The company also added a ludicrous 16:9 aspect mode: not only does it simply crop and letterbox the standard 4:3 image, but the LCD is too small for a functional letterbox display. More useful is the new 320x240-pixel 60 frames per second movie-capture mode, which produces slick little movies, as does the VGA, 30fps mode. Unfortunately, the camera still lacks raw format support.
Oddly, despite the different sensors -- or perhaps because they use the same f/2.7-to-f/3.5, 36mm-to-432mm lens and Digic II imaging processor -- the S3's photos look almost identical to the S2's. They display a broad tonal range, albeit with some clipping in the highlights and shadows, very good colour accuracy and saturation, and acceptable edge-to-edge sharpness. Its noise profile follows suit as well: low until about ISO 200, then increasingly bad. Though the camera can now boost ISO sensitivity to as high as ISO 800, either manually or by enabling ISO Boost in a programmed-exposure mode, the noise at that setting is quite obtrusive. In general, the S3's photos look good but can't really shake the digital look, either onscreen or in print.

Performance, while not identical to the S2's, is either the equivalent or better. Start-up to first shot takes only 1.5 seconds, which is quite zippy overall, and extremely good for a camera that has a long lens to extend. Shutter lag in bright light reaches about 0.4 seconds and doubles to 0.8 seconds when the lights get low. The S3 is also relatively responsive: 1.1 seconds typically from shot to shot, plus another second if the flash needs to recycle. Though it maxes out at 1.5fps in continuous-shooting mode, there's no buffer-constraint on the number of sequential shots at maximum resolution. We find that much more useful than a fast but limited burst mode. It was certainly sufficient to capture active dogs and children playing in the park, including children spinning on a tyre swing.
Autofocus occurs quickly for the most part, although a few of our shots looked as if the focus hadn't locked before capture. We didn't experience any of the problems that we had with the S2's SuperMacro mode -- it worked fine for us, even with the lens almost pressed against the subject. The image stabilisation bought us about two stops of shutter latitude, but our hands shake like an octogenarian's -- a coffee-drinking octogenarian.
We're not big fans of electronic viewfinders, and the S3's didn't convince us otherwise. Though it's fine for framing, we hate that it freezes when the shutter is pressed. The LCD is certainly viewable in most light, but we prefer an eye-level viewfinder to the unsteady arm's-length approach.
