I made the mistake of upgrading from Microsoft Windows 7 64 bit Ultimate Edition Service Pack 1 to Microsoft Windows 8 Pro 64 bit last month. Curiosity killed the cat in my case. This is not to say that I am in a world of hurt with Windows 8. I only had one problem during the upgrade process while trying to preserve my old software applications, settings, and user files so I ditched it for a clean upgrade.
Windows 7 64 bit still makes a lot of sense even in late December 2012. Getting a traditional desktop environment to work properly on a daily basis is challenging enough. Windows 8 Desktop is a mess. There are too many hot corners and pull-down or swipe across side menus. The Windows 8 Modern UI is pretty clever. It's pretty functional and smooth in action, but the Windows Store lacks compelling apps. It makes the Modern UI seem lacking in high quality apps right now.
If Microsoft had just devoted itself to making Windows 8 all about the Modern UI and they completed ditched the desktop, then it would have saved them a lot of trouble down the road. The days of the traditional desktop PC user are fading fast if you are a Microsoft customer. Windows 8 is an early preview into the future. Traditional, locally installed, software applications are out of fashion and a curated Windows Store and cloud centric apps with in store payments and subscriptions are the future.
Microsoft may release a new version of Windows annually starting in 2013 with Windows Blue. This is not yet confirmed. If it is true, then they may charge a nominal fee for the privilege to upgrade to the latest and greatest Windows versions annually. I don't know how this is going to sit with their enterprise customers that demand conservative stable production environments, long term support contracts, and predictable future.
Windows 8 is not catching on too quickly, but it's early right now to say for sure. There aren't enough Windows 8 developers to make the Windows Store appealing enough right now. The operating system itself is not a killer app.
If you have Windows 7 and you are happy with it, then stick with it. It may be the last version of Microsoft Windows that you will want to keep using until the end of 2015 if you don't like major changes to your desktop.