My wife as an educational version of Office 2008. It works and is compatible across most boundaries. But after using certain elements in iWork, it is cluttered, but not as much as the Windows version which lacks explanations for icons. Visuals visuals visuals - sounds like a battle cry from 1995!
Office 11 for Mac looks to get even more cluttered, but at least the new 'vista strip' or whatever it's called has some letters in there too so users can sink their teeth into something realistic. Icon's don't explain everything and grouping of a million items into one is pretty time-wasting.
Anyway, looks like Mac users won't have to wait 4 years in between updates again, but will Office 11 be worth it?