Zach, I believe you have said that Nikon is worse than Canon regarding noise. Do you think increasing to 10MP on a chip that has noise is going to make it worse?
Same as film, cleaner image and slower shutter speeds. I have ISO 100 on my Canon and sometimes wish it went lower, but I also want clean images at ISO 800 and above when I need them (low light and fast shutter speeds), which I often do shooting wildlife.