Still the bottom line is that you'll be choosing between windows and osx. Windows 7 is definitely an improvement not only over Vista, but also over XP. It is not an improvement over OSX, even with the added eye candy MS added.
I use windows at work, and have a win7 install for work related stuff. I much prefer how OSX operates, its much more consistent and seamless. Lack of malware is a huge plus and the general interactions is superior.
With that said, its all personal preference and MS is trying to keep the undecided from checking out apple, since apple's market share has been increasing.