The only Mac experience I have personally is a core duo version (one of the first intel MacBook Pro) and then listening to the coworker's air. I'm glad to hear that newer ones are quieter, and that's definitely going to weigh in on my next "workhorse" laptop.
Cool. FWIW, my retina MBP idles around 45 deg C, goes up to about 65 when watching a Flash video (maybe 55 for HTML5 video), and as high as 90 deg C when playing XCOM in Parallels (at which point I manually crank up the fans because OS X tends to prefer heat over noise and I do not).
