So I've been drooling a little over the PowerShot G9 as a good point & shoot camera for times when I don't want to use an SLR. But then I thought, if I'm going for small and convenient, why not one of the ultra compacts (e.g. an SD950 IS)? (I'm using mainly Canon here because that's what I'm most familiar with, but I'm considering others too). How does the image quality of these ultracompacts compare with their slightly larger point & shoot siblings? Obviously it can't be as good a camera, but just how different are they? I've seen articles comparing the G9 with DSLRs, but I haven't seen as many direct comparisons of, say, G9 with sd 950is (or similar comparisons with other manufacturers).