I just ran the updater for AVG Free 7.5 on my XP computer and after it downloaded I was notified I had to reboot to complete it. I have had to reboot after an update before, but it has been some time, still I really didn't think anything of it. Then I decided to run the updater on my other computer running Vista. With that computer, I didn't have to reboot. I asked my dad to run the update on his computer and he didn't have to reboot either.

Computer 1 XP Home SP2 - Reboot Required
Computer 2 Vista Home Premium SP1 - No Reboot Required
Dad's Computer XP Pro SP2 - No Reboot Required

With my second computer and my dad's, was the reboot not required because of the different operating systems? Did anyone else with XP Home have to reboot after updating to database version 269.23.14/1425? This probably isn't anything to worry about, I'm just curious about these sort of things.