iWork '09

Pros: All the power most users will ever need
Keynote beats Power Point hands down

Cons: Some of the formatting doesn't port well to MS Office

Summary: For the price you'll be hard pressed to find a better suite to use for the Mac. It's quick to open, full of features and solid in operation. I'm not a heavy spreadsheet user, but Pages and Keynote absolutely are worth the money, and Keynote is a dream to use. The review stated that MS Word has better layout features, but I don't see it. In fact, I do better with Pages than Word in the layout.
If you don't have to have Word/Excel you owe it to yourself to try it out. The only reason I didn't give it a solid 5 star is some trouble I had porting some documents over - not all the formatting transferred as well as I would have liked. Other than that, no problem and worth the money for a native Mac program.