I use Photoshop 7.0, I use it because it is much better than any other 2D Program I have tried. That's my opinion anyway.
My reasons for thinking it's better are,
- You can create very large images with ease
- There are lots of cool preset actions (I never use them but at least they're there)
- Although it doesn't have brushes like ropes in Paint Shop Pro, it still has some pretty cool brushes