I have read been reading a lot of good things about OSX 10.8 Mountain Lion. But I have also seen a few things from others that do not really like some of the things that are required and/or being published with Mountain Lion, but I was not able to see why. I am not new to Macs, but I am a baby when it comes down to the tech information. What are some issues with Mountain Lion that would make we second guess about the upgrade? Also, should I format my HD and then install Mountain Lion? If I do format the hard drive, will I need the product codes for my programs that I did not buy via the app store (using time machine to restore all my documents and programs)?