I have a 21.5 inch, mid 2010 iMac with 12Gb RAM and since installing ML my mac seems to become really hot. If I run my hand over the top of the machine the centre and left corner are really hot. Not just warm but sometimes nearly too hot to touch. ML has been installed now for 72 hours. Has anyone else noticed a huge increase in housing temperature since upgrading? Is this heat excessive and likely to damage my iMac? I think the problem of not being able to 'sleep' without losing network connections (so being left to run permanently) is exacerbating the problem.