After using Leopard since Friday afternoon, I hate to say that I'm not overly impressed. While there are tons of things I have yet to try and discover, it just doesn't justify the price and hype for me. Haven't tried Time Machine, or Spaces (no need). Not too impressed with the Finder, although Quick Look is cool, you can't browse multiple pages while you are "quick-looking" a document. Finder only uses 1 view for all folders, 3D dock is a bit distracting, Safari is slow on some sites. I think I'll be writing my own review on this, on both good and bad aspects.
In a nutshell: Should you upgrade? Not if you're happy with Tiger - at least, not yet.
In a nutshell: Should you upgrade? Not if you're happy with Tiger - at least, not yet.