Bill, when I upgraded my folks eMac from 10.2 to 10.2.4 I ran the permissions update and it must have worked on nearly every file in the machine. It took more than 10 minutes to run.
If repair permissions has not been run for a long time, it takes a long time to do its job. I had never ran it until a couple of weeks ago and it took nearly 20 minutes. When I reinstalled IE it only took 1-2 minutes.