If you've upgraded to Snow Leopard, there are two things you may not have done.
First, use the Mac OS 10.6.4 combo updater. This fixes a problem with the Hoefler Text font that is not fixed using the delta update (10.6.1 > 10.6.2).
Second, make sure your iWork applications are updated. For iWork '08 that is Pages 3.0.3 & Numbers 1.0.3. For iWork '09 it's Pages 4.0.3 & Numbers 2.0.3. If you're not running the latest versions & Software Update says your software is up to date, make sure the applications are where the installer initially put them. The updaters are very picky. If the location is not where the updater is programmed to look or if the folder doesn't have the name the updater looks for, it will not work. The applications cannot be renamed or moved. They must be in the iWork '08 or iWork '09 folder in Applications. That iWork folder must be named iWork '08 or iWork '09. If it doesn't have the '08 or '09 Software Update won't find them & the updaters won't work.
