Greetings!

While I know almost nothing about cameras, I can help a little with the memory. SD and MMC memory are the same form factor and connections, so the devices I have tried can use them interchangeably. SD can be purchased in much higher capacities (up to 512MB). Your milage may vary.

I bought a 128MB MMC card when I first got the Rio S50. This was before I knew that I could use SD memory and that there was a 512MB SD card out. (There was a posting in the web site thread that the S50 page really needed to be updated to show the expandability. I agree completely!!!) If you are interested in a 128MB MMC card cheap, send me a PM.