The G10 is physically quite similar to the G9. At 14 ounces, it's heavier by about an ounce, and it's also a bit bigger one to three tenths of an inch on all sides, for dimensions of 4.3 by 1.8 by 3.1 inches. As with its predecessors, the Canon G10's metal body feels like a tank. I'm beginning to wish for just a little bit more grip, though, especially since the thumb rest feels kind of slippery. The dial configuration ranks as the most notable change to the design.
Canon stacked the mode dial inside the ISO dial for right hand operation and added an exposure compensation dial on the left. It retains the four way switch (for setting manual focus, macro, flash, and drive mode) with a Function or Set button nested inside the navigational scroll wheel on the back. And though the focus point, metering, display, and menu buttons remain in the same positions, they now have an odd, angled design.
Overall, I like the changes, and shooting with the G10 feels quick, fluid, and comfortable. The optical viewfinder is relatively large and distortion free, making it quite usable.Though Canon giveth with the improved wide angle coverage, it taketh away in total zoom range. The new optically stabilized f/2.8-4.8 28-140mm equivalent 5x lens should please landscape photographers, but some folks will miss the 210mm equivalent reach of the G9.
That and the move to a 1/1.7 inch 14.7 megapixel CCD from a 12 megapixel version constitute the most notable feature changes. At least they haven't taken away the stuff I liked in the G9 the built in neutral density filter, two slots on the mode dial for custom settings, ability to change the size of the AF area, a hot shoe, exposure lock, raw support, and the bayonet adapter mount that help distinguish the Canon G10 as a camera for enthusiasts.
The addition of Servo AF is nice as well, but it's odd to use while holding the camera out for LCD view, and unlike on an SLR, there's no focus area confirmation in the G10's viewfinder. I think it'll take some getting used to.
