IMHO, I went with the MC200. The form factor seems smaller and the still shots have a slightly better resolution that the MC100.
With the image stabilizer and LCD screen, taking video is a snap and the quality is awesome.
You will be impressed the quality of the still shots (can't compare to a true digital camera) but I have had stills printed to 3x5 and they look great! Go to (homepage.mac.com/pjmurphy77) you can see shots of my Powerbook.. those were taken with the 200MC.
Another small benefit is I can use firewire for both downloading video and stills from the camera. Some cameras make you switch between USB and FW to download items..
If you have specific questions, let me know...