The reason there is no way to se it is because very few apps CAN run in the background. Most are paused or frozen, aside from apps like navigon, pandora, iPod etc. so the list is usually enough. If only 5 apps can run in the background you don't really need a task manager--just close them out through the app switcher and they will quit.
iPhone 5 ✲ iPad 3 WiFi ✲ Macbook Pro running Lion 10.8.2 ✲ Xbox 360 ✲ Nintendo 3DS ✲ PS3
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