mvas457,
I normally have my clients communicate every 3 hours, but for PCs I schedule for VirusScan upgrades from 7.1 to 8.0i, I've set communications to occur every 10 minutes and to perform a full inventory scan. Usually after the 8.0 upgrade, I get both 7.1 and 8.0 showing up in the Properties, but if I wait long enough, the client eventually shows only 8.0. Like Xavier2 said, you can do an Agent Wakeup Call and it will speed up reporting.
Of course, I've also encountered cases where it will always report both 7.1 and 8.0 and physically checking the PC also shows both 7.1 and 8.0 files, which meant a full remove and reinstall of VirusScan.