Good question and to be honest I have really started looking at Linux full time with maybe just a windows vm running with in it. My co-workers all use mac book pro with windows 7 vm's and are extremely happy. I guess I can only thing of three reasons to go to windows 8.
64 bit support for virtual machines. (although I do sorely miss the vm integration features windows 7 offers).
Play around with creating FKMA's (formerly known as metro apps) in visual studio 2012
I bought a second ssd to install windows 8, so my windows 7 system is only a reboot away.
I also have another windows 8 tip. How to disable the lock screen:
Computer Configuration -> Administrative Templates -> Control Panel -> Personalization