Just learnt from hard experience the performance difference between the vanilla javascript innerHTML property and jquery’s html() method.
For Firefox 3.6 it was not so bug, just maybe 50% but for Safari the difference was several 100% (!). For Google Chrome, the difference was somewhere in between. All this is for a pretty large chunk of html and has been tested on Mac OS X. In usability the difference meant not being show a spinning beach ball in Safari and for Chrome not being asked whether it should terminate the script.