This is one of the items that is tested in your Windows 8 App when you use the WACK.
If you are in Southern California, please email these posts for more information on getting a token for your app by June 30, 2012!
An application has five seconds to save state after the suspending event fires. The application should resume just as efficiently. References: Optimizing your app's lifecycle
Reference (HTML)
Optimizing your app's lifecycle
Reference (XAML)
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