I have an iMac G5 iSight here who's memory controller was sitting at over 60*C at idle. I don't think you're too far off the mark.

Incidentally, I have repaired a lot of these iSights that have had bad capacitors on the back side of the logic board, behind the memory controller's heatsink. They all have been of the "bad cap" types and are in a high heat area which, I'm sure, is why they fail regularly. To my knowledge, Apple never offered any sort of warranty extension for these models.