Go figure...
Silly boy, that's easy to figure.
As a heavy user of GTM on both Windows and OS-X for many years, I'll tell you that Citrix' support of the Mac was weak, late, and incomplete.
(Say, that couldn't be because Citrix has been in bed with Microsoft for years for RDC, could it? Nah, mere rumor...)
Nevertheless, the GTM audio quality on a Mac the last year is consistently better than on a Win-PC. There is one nagging visual artifact on the Mac that I bitch to Citrix about regularly. Other than that, both work fine.
All I know is that when I call a conference meeting of my employees through GoToMeeting, it is always the Mac people that have the problems connecting in.
Go figure...
*****************
There was a long discussion on useNet long ago about whether Mac or Atari ST users were more clueless.
Finally, someone settled the matter by saying: [The Atari ST user base is 1/100 the size of the Mac user base, and EVEN THEY managed to scrape together the clue to do a port of gcc.]
Those days are over. Clue-less and clue-ful people use Macs.