Photos from the G1 are good for snapshots at small sizes; poster-sized prints and heavy cropping is probably out of the question. As with most point-and-shoots, quality drops off above ISO 200. The bigger problem is that subjects have a decidedly digital appearance. Add to this the increased noise and noise reduction from ISO 400 and above and your chances of getting a sharp, detailed photo are almost nonexistent. Of course, these issues aren't as visible at smaller sizes, say prints at 5x7 inches and below, or when viewed at similar sizes on a computer screen. Also, beware that with the starting aperture of f3.9, low-light situations will force you and/or the camera to use higher ISO settings or the flash. There are noticeable color issues at ISO 1,600 and ISO 3,200 due to noise and yellow blotching.
This shot was taken using the camera's Underwater scene mode to capture "all the colors and hues of the underwater world." Captured at ISO 1,600, the fish doesn't really have any detail to it and--though it's not visible in this 100-percent crop--neither did the rock. Everything looked pretty flat. Colors were good and natural, but only when viewed at small sizes. They'll be fine for online sharing, but not much else.
Purple fringing is above average for its class. You can see the building and statue are outlined in blue/purple fringe. Lens flare was also an issue, likely because of the tempered glass protecting the lens.
For not being a wide-angle lens, the G1 has some visible barrel distortion (top). Even when the lens was zoomed out there appears to be a little distortion on the left side of the lens. The lens isn't terribly sharp, but it's decent and consistent edge to edge.
Colors are very good and pretty close to accurate--at least below ISO 800. White balance was similarly good indoors and out. If they aren't vibrant enough for you, there are controls for fine-tuning saturation, sharpness, and contrast.