I think you are confusing telephoto for Macro. They are not one and the same. Both of these cameras also lack RAW capabilities. Without proper white balancing your tank is going to look blue.
The Canon G10 and Panasonic LX3 blow both of the above mentioned cameras out of the water. Between those two I think the G10 reigns supreme for reef tanks. In some other applications the LX3 would do a better job. DSLRs can change lenses, allowing the photographer to tailor their equipment to the job at hand. This in turn allows many equipment configurations tailored to a specific goal. Point and shoots are geared to accomplish a wide range of tasks with once piece of equipment. This sacrifices convince for quality, but they are obviously MUCH less expensive as well.
The Canon SX10IS and Nikon P80 are geared for telephoto: planes, birds, football players, and other subjects which are FAR AWAY. In turn these cameras are NOT geared for up close and personal subjects, which is to say macro. This is not to say these cameras are incapable of closeups, just as an LX3 is incapable of shooting an air show. Just because a camera *can* take a picture of something doesn't necessarily mean it can take a picture of something well.
So the question is what point and shoot, geared for a wide range of subjects, is best geared for reef tanks? I would say the Canon G10 hands down.
