My enterprise is not even considering Win 8. We have 5000+ PCs to manage and there's no business reason whatsoever to upgrade. It was hard enough to get our users to deal effectively with their upgrade to Office 2010...(who moved my cheese!) Windows 8 would grind the company to a halt.
If you run 7, stay on 7.
If you're getting a new computer, don't fear 8, though it will take a little time getting used to.
If you have a corporate office and will be replacing 500 pc's, you better do some tests with your users before you even think about 8.