Pretty interesting. Somewhere out there, there are comparisons between Apple's power adapters and knockoff ones, which are very poorly engineered in that case.

Also, as it happens, Internet lore is correct and every Mac I've tried the USB adapter on running 10.6 and later can use it just fine. (I may or may not have used it to help break some EULAs, in my own time, off of this site.) It also works on Apple-branded Macs. running 10.6 or later, although I have not tried it with 10.5.