Why? Because of "Get information about the currently or recently running tasks: a thumbnail representation of the tasks, what activities are running in it, etc."?
It appears GET_TASK may be used to prevent ad loading when the app is backgrounded. Mobclix.
Also, it appears if I remove the Amazon App Store app, some apps simply refuse to let you run them, asking for you to launch the Amazon App Store. I think the Amazon released apps, some of them, may be phoning the mothership. I am not yet concerned or paranoid enough to sniff the net traffic with a proxy.