Yeah this is a problem at the moment as none of the offical clients support video between PC and Mac. She can use ichat but that only works between macs. Microsoft have refused to enable video chat for mac. Yahoo does seem to allow webcams
There is mercury messenger:
http://www.mercury.to/
But i do not think that works correctly yet. Only from pc to mac but not the other way yet.
The best client imo is adium, no A/V chat but it is the best:
http://www.adiumx.com/
It works with msn and yahoo and you can have multiple accounts running at once. Plus it has tabbed chat. also:
http://trac.adiumx.com/wiki/VoiceAndVideo
Otherwise wait until Skype release video chat for mac. Sorry. Good luck to your daugter with the degree, i am doing same sort of thing. Also welcome to the world of macs
