I have an SD400. Overall, it's a great camera, but I'v noticed that with most Canon point-and-shoot's, indoor photography is not their strong suit (still not bad photos). They are fantastic outdoors. I still am loyal to their SD line, because there really isn't a combination of compactness, performance and quality on the market that comes close.

On a side note, I think Nikon's are fantastic (what I use for my SLR), but they are by no means user-friendly. Defienetly not the camera maker for casual use.