I ran across this this morning (see YouTube video).
A very cool comparison by the very knowledgeable techy’s at PCMag.com showing the video call quality between Skype and Facetime.
The test was completed via WiFi since Facetime is limited to that transport mechanism.
My issue with Facetime is it’s limited call-ability….it works fine between other iPhones, or Macs, but, that is it. The world is bigger than Apple.
On the other hand, Skype is multi-platform, allowing you to connect to many more family, friends, colleagues. And, soon, via cloud video conferencing applications, to corporate H.323 videoconferencing rooms, desktops, etc. (yeah..that is a scoop)
Soooooo, even though the video might be one factor, usability and connect-ability are also factors, and, IMHO, more important factors than video quality.
From experience: Proprietary video conferencing products always had better video quality, but they also did not last. The list of now dead proprietary systems is long, and their remains litter the videoconferencing highway.