Apple Special Event live stream

One other thing about the iMacs vs. Towers that concerns me is cooling - there was that one generation of iMacs that all were really prone to overheating (in my soph. year of college like 2/3rds of the iMacs in the MIDI lab had to be replaced under warranty for that reason), and sometimes for no reason the fan on my dad's iMac (which he bought last January) will just start roaring, and the only way to shut it off is to put it into standby and then back out. My understanding is that two computers with identical specs won't run the same if one is better cooled than the other (or if nothing else, it makes me worry about the reliability...)