I only use Skype for its Mac/PC audio-only conferencing, which works very well. I don't use it for instant messenging because I have iChat and MSN. However, this will become redundant once Tiger apparently adds audio-only conferencing between iChat and AIM 5.5 for Windows.
Skype for Mac is currently a beta and has problems when an audio conference with 3 or more people in it is executed. My experience (2 Mac people and 1 Windows PC) ends up with echoey chaos. Also, there seems to be a bug with respect to PC users recognising when Mac users are online.
Skype for Mac is currently a beta and has problems when an audio conference with 3 or more people in it is executed. My experience (2 Mac people and 1 Windows PC) ends up with echoey chaos. Also, there seems to be a bug with respect to PC users recognising when Mac users are online.