If anyone wants to go one step better than iStat and actually test how much heat gets transferred the surfaces we humans TOUCH, grab an Infrared heat gun like this:
http://www.amazon.com/Fluke-62-Mini-Infrared-Thermometer/dp/B000MX5Y9C
That's similar to a IR thermometer I actually took into the Apple awhile back to Mac sure I wouldn't get a computer that scorched me. I really don't think the Macs from the past few years have as much of a problem, though.
The thing is, you do get "lemons"... These things are made in China, after all, a country which has proven that it will kill children and seniors alike by putting melamine (basically powdered school table) in milk if it means saving a few cents.
http://www.youtube.com/watch?v=ZBpAknlu0TE
This is a country that desperately needs to return to it's vastly more ethical roots.
True lemons aside, in my in-store IR testing of Macs, I saw all the computers were a bit different temp wise, even from a fresh boot...
The sloppy way the $120/mo Chinese (slave or pseudo-slave?) workers apply thermal paste has a lot to do with this. I'm guessing the folks over at PC Authority in Australia got a machine with too little or too much (more likely) thermal paste applied, which made their computer excessively hot. They should exchange it. Apple, btw, will easily exchange anything the moment you whip out your IR gun to prove a point.