One of the G series' main attractions was its flip-and-twist LCD. That's gone in the G7, replaced by a bright but fixed 2.5-inch LCD. The rest of the top and back of the camera body bristles with controls, leaving just enough space for a decent handhold. Those with large hands, however, may find it difficult to firmly grip the G7 without accidentally covering one button or another. (Take a tour of the body.)
Canon packs its newest features into the G7, including the same 10-megapixel CCD that's in the SD900, its Digic III processor with face-detection focus and a 15fps XGA movie mode, and an f/2.8-to-4.8, 35mm-to-210mm-equivalent (6X) optically stabilized lens. Unfortunately, whoever at Canon decided to jettison raw-format support deserves a whack upside the head. Aside from that, it offers all of the exposure, focus, and shooting controls any enthusiast would want. They include a spot meter, user-selectable focus zones, two custom settings modes, continuous- or shot-only IS settings, manual ISO settings up to 1,600 plus a High mode which reaches up to 3,200, voice annotation, and a hot shoe.
Not everything functions the same as in other Canon models, and that can be a bit disorienting. For instance, the addition of face detection has complicated the focus-zone selection, since you configure both options from the same screen. And it's a little frustrating to have to use the up/down/left/right controls to slowly navigate your way to the desired focus zone, rather than using the scrollwheel to just zip over to it. Once I got used to the interface, though, it stopped interrupting my shooting rhythm as frequently. (I need more time to evaluate the face-detection performance.)