One of the new core technologies in Mavericks is called "App Nap" and as its name implies, an application that is not visible or apparently active will "nap" or go into app-specific "sleep", wakened when it's brought to the front/visible, etc.
Get Info (Finder command Command-I) has the ability to "disable app nap" in its General section near the top of the Info window, so Mavericks gives users the ability to disable the feature on an app-by-app basis. Checking the box disables the napping.
Would it be advisable to disable App Nap for Fusion, of any version? I could see use for this, say that a nap might disable something like an overnight Windows Update, Windows Backup, virus scan, or other nighttime maintenance task. Or would such a scheduled task wake the app from the nap without having to go to that end?