Canon 650IS or 720IS - Image Quality

No. In fact, since the majority of your shotss are 8x10 and under, a 12MP camera is actually overkill. For picture quality, I think there's too much MP there to work with. Although you do have a point that it has a larger CCD chip. But I think that is balanced out by the fact that the 650IS is less MP on the smaller chip.

Let me explain. I came across an interesting article today about how more mega pixels is not necessarily a good thing. According to Image Engineering – a company that does testing of digital cameras for photo magazines in Germany – the quality of digital pictures has steadily decreased since the state of the art was six megapixels back in 2004. And because they don’t have a “dog in this hunt,” they put forth a compelling argument for buying new digital cameras with less mega pixels and not more.

The argument is essentially this: CCD chips on point and shoot cameras a smaller and as such, fitting in more pixels causes them to lose light sensivity. Sure, there’s more data on the chip, but the chip can’t absorb the light data and what it ends up with is a picture that has more noise than image quality. In addition, the more megapixels a camera has, the larger the lens it needs to provide the clarity it deserves and prevent diffraction due to a loss of detail with smaller apertures. But since we’re talking portable point and shoots here, those large lenses simply aren’t being made.

Finally, with larger mega pixels comes longer saving time due to their requires huge storage capacity, or more compression if not storing images in RAW format. The result is a noisier image and a dissatisfied camera user who thirsts for high quality and speed but fell into the trap of "more must mean better."

In the end, relying on a smaller MP that can balance all these needs may indeed be a better answer.