The guy at the apple store said that the iMac's HD's are gaurenteed to at least be 5400 rpm HD. I check out mine through the Apple System Profiler and I have a Seagate ST360020A, which is 5400 rpm, which specs are here:
http://www.seagate.com/cda/products/discsales/marketing/detail/0,1081,373,00.html
Please post if you got a 7200 rpm model.
http://www.seagate.com/cda/products/discsales/marketing/detail/0,1081,373,00.html
Please post if you got a 7200 rpm model.