> In fact, those with headsets will sometimes be worse because they're making a lot of mouth sounds close to the mic.

Yes this also freaks me out. Also when people use headsets in a room with lots of background noise, it sounds as if they use an open mic.

I'm also quite convinced that the Mac with just the internal mic/speaker is quite good for most cases. But I definitely want to look further into the issue. Also I certainly don't want to use a dedicated external mic, that seems total overkill to me.