I upgraded my home machine from XP to W7, because I was curious about it. I can't tell that there is any big advantage to it over XP. It seems to run well and looks pretty. I still run XP on my work computer so in effect I use both OS's every day. I also have a laptop with Vista, another laptop with W7, and a tiny box with OSX on it.
If you had a need to more than 4GB of ram, then I would recommend W7-64bit over the previous versions.