Reading this article inspired me to do some followup research, ending with my own SL300RT* showing up today :-) It makes a worthy replacement for the Canon S200. I haven't missed the tripod mount - shooting with the camera "flat" makes up for it, and actually takes better "dashboard movies" than I'd ever managed with a conventional mount. The ability to directly couple to a 28mm ring is a major win, even if the adaptor is plastic - it works surprisingly well with an 8x zoom scope for extra range. (Google even finds one site with one of these cameras on a real telescope, taking moon shots in daylight...)
The one thing I'm still looking for - the S200 (and S110) could store an "owner" name in an EXIF tag - it was a convenient place to stuff an email address, especially for photos that circulate on the net. Having a "real" USB connector and generic drive mode is more than worth it, but is there a trick I've missed, or is tagging afterwards the best I can do?