Hey guys, Firstly, a belated merry christmas to you all, and best wishes for a happy new year! Now, on to my real question: Mountain Lion has been out for some time now, and as yet, I've not upgraded. This is primarily due to the fact that the App Store sports some disturbingly lousy Customer Reviews of the new OS, and I wasn't prepared to spend the money if it wasn't worth it - to paraphrase one reviewer, I don't want to install an operating system that resets my screen brightness setting every time it reboots! Also, there's nothing wrong with Lion as it is at the moment, by which I mean that irrespective of personal gripes, the system is running as efficiently as ever. I own a mid-2010 21" iMac. Basically, I was wondering if anyone out there has run the upgrade on this platform and, if so, whether or not you would mind giving me a few pointers - smooth upgrade, any bugs at all, system instabilities that result - and whether you'd recommend it? Thanks in advance!