And Apple already has some good examples on the web
There’s a new app switcher concept on the web that Apple could well implement in iOS 7. Posted by Verge user Sentry, the concept shows how Apple could leverage the extra vertical space on the iPhone 5 and iPod touch (fifth-generation).As the image above shows, instead of showing just the application icons, the multi-tasking tray could easily display previews, or snapshots, of the running apps themselves, giving the user a better idea of what to select instantly.
In another embodiment (patent filing talk) this new task manager would enable users to easily access core system functions, such as the orientation lock, wireless functions, and the display brightness.
Lastly, the same concept can be applied to the Music application. A simple swipe to the left or to the right would bring up a few handy playback controls complete with album art and a volume knob.