DPReview now has a full review of the Canon S5, the successor to the S3 that I have. I've played with the S5 in a store, and I'm not impressed, especially since the S3 costs half what the S5 does right now. The big turn-offs for me are the card access (in with the batteries), and the slower burst speed. There are plenty of comments going up right now in the Canon forum.

I currently have a Canon S3 that is a year old. Next year I expect to replace it with something else (no clue what yet), but if I were in the market right now, I would be looking at the Olympus SP-550 UZ. That's the ultra-zoom camera with the 18x zoom lens. Dpreview.com now has a full review of the Olympus. The only direct comparison to the S3 comes on page 17 where the resolution charts are shown.

High points for me are that the lens goes wider and longer than the S3 and it takes AA batteries. On the down side, there is no flip-out screen, and it's not all that fast a camera. You can't use sound in a movie if you want to zoom. It does RAW, but I don't believe is supported by Aperture.