Yep, the BootCamp vs. supervisor software (PArallels, Fusion, etc) really does come down to what you'll do.
Any software that needs direct access to hardware--including high-end 3D games, high-end rendering software, and so on--will run much better under BootCamp. With BootCamp, you boot "pure" Windows. You're not running OS X at all.
Any situation where you want to run Mac and Windows apps side by side, or trade data easily between Mac and Windows, or use the same files with Mac and Windows, you're better off with a VM supervisor like Parallels or Fusion.
I use Parallels, myself. It works fine for light gaming, for productivity apps, for Internet, for Office, and that kind of stuff. I would not try to run AutoCAD or new, modern 3D games in it, but for 95% of the stuff out there it's awesome.