WebRTC might be cool, the demo looks cool, but the official site says that it might break or go away anytime and - please, please, please never ignore this - only one single browser seems to support that tech.
Fool around with it, but this can _never_ be part of a Skype killer until everyone can use it.
step 1 - download dev version of chrome into a separate folder
step 2 - enable webrtc in flags://
step 3 - put a shortcut on your Desktop that points to this and says "Skype-NG" or something like that.
How is that different now than going and clicking on Skype from running and launching point of view. Bonus points, can also browse the web if you want.
Skype also might break or might go away anytime too. Or, rather, more likely will interrupt your video stream every 5 minutes to show you adds about dating sites and Nigerian scams.
1. download some 1MB binary. No depends or 3rd lib runtime or shit.
2. BAM! Voice and video group chat. S2S federated with all other XMPPs.