It became necessary for work-related reasons that I should attempt to install Skype on my home computer, so I made the attempt.
It turned out to be remarkably easy. I bought a USB headset and downloaded the application. I already had a Web camera, and USB drivers for it and the headset. Getting it up and running proved to be just a matter of plugging in the USB devices, loading their kernel modules, unpacking the tarball, and running the application. It ran right from the unpacked directory without needing further installation.
So, now it appears I can "chat," even with "video." If anybody really wants to do that with me, they can email me and maybe I'll tell them my user name. I don't expect to do it frequently, though, nor to leave the application running in general except when I have a planned call. I got it for work, and prefer email for personal contact.
ETA: this was actually part of the reason for posting, but I forgot it in the initial round: I found out that one of my postdoc applications was declined. This one was my first choice, and if accepted would have kept me in Toronto until late 2012. I have others possibilities under consideration, but the chances I'll stay here are now somewhat reduced. I have mixed feelings about that. I hate moving, and I really like living in Toronto. On the other hand, in a year and a half here neither my personal nor my career goals have really been met. It's not clear whether I'd really be allowed to expect things to be dramatically different in two future years, and if not, and if I could leave to somewhere where it would really happen, then that would be better.