Ok so I have now confirmed that my problems are definately heat related.
I am running WoW on an iMac G5 intel.
Here's how it is.
My iMac starts to have problems with WoW when the CPU temperature reaches approx 50ºC.
The iMac's fans don't ramp up to cool the unit until 65ºC
What we need is a widget that allows us to control our fan speeds.
This free little widget places the cpu temperature and fan rpms in the menu bar at the top of the screen. The widget also checks for updates on its own, and allows you to make custom profiles.
Turn the fans up for gaming, turn them back down when done.
Simple as that.
I am finding that with the WoW's FPS throttled to 35 and the fan speed set to 5000 rpm I can run all the graphic features that the 2.4 update has brought to the table. The CPU hums along at about 42ºC.
To set your fps to 35 use this command in-game:
/console maxfps 35
And if you use it please show the author some luvin', toss him a few bucks via paypal. It'll encourage updates.