With Skype the most important thing is your connection. If you have a decent line speed then you are sorted, otherwise lots of buffering can occur (especially on video calls).
Spoke to Jnr in Los Angeles on Boxing day. Built in web cam and mic, so low pixels. Don't know what he was using. When he uses his built in web cam, the quality is fine. Connection speed is most important for quality. Top site IMO. Science fact not fiction.
I use webcam and separate mic, but one thing that occasionally screws things a little is when the other party gets echo from my speakers. Headphones would of course, eliminate that glitch.