I have Windows 7 installed in Boot Camp. While I absolutely don't mind starting afresh, it will save me a lot of trouble if I can upgrade the installation to Windows 8, now that OS X 10.8.3 has Windows 8 support. I have a downloaded copy of Windows 8 with a product key.
MacBook Pro (13-inch, Mid 2012), OS X Mountain Lion (10.8.3)
I remember that Apple released upgrade utilities to upgrade to Windows Vista and Windows 7 when they were released. This utility unmounted the OS X partition during the whole upgrade to prevent problems. Apple hasn't released this utility for Windows 8, so I understand that it's not recommended to perform an upgrade. In conclusion, you should make a clean install, just in case something goes wrong and you lose files from the OS X volume
Can I upgrade an existing Windows 7 Boot Camp installation to Windows 8?
