I use both PC and Mac, on which I have upgraded to Windows 7 and Snow Leopard respectively. (I also use Ubuntu, Debian, etc.) Windows 7 is the best OS I've ever used.

Snow Leopard is really just the previous Mac OS with some refinements. Windows 7 is a next-generation OS. Similarly, Internet Explorer 8 is the most secure web browser, and in many real-world scenarios it's also the fastest. (E.g. IE8 loads Google's homepage faster than Google's own browser, Chrome.)

I can understand people's caution when upgrading their OS. But Windows 7 is a good move.

However, my advice would be to wait a few months for the hardware to catch-up. Many people buying Win 7 now, especially Vista machines with an option to upgrade to Win 7, are getting a next-gen OS on current-gen hardware. Win 7 supports much better hardware specs, so you might as well wait for the manufacturers to start making use of it.