The tradeoff is that the larger the picture the slower the frames per second transmission rate. The basic software that comes with the QuickCam is more than enough to get you started. The disadvantage to this is that you need a video capture card and video camera. All this for color which only increases the load on your internet connection and slows down transmissions. There is so much more to tell but no more time and space to tell it.
Internet telephony is a brave new world.
I strongly encourage anyone embarking on adventures in cyberspace to find friendly guides to help you on your way. In this matter, however, I haven't found cyber-surfers to be particularly accommodating.