I'm not sure if anyone here has used the BB Playbook (and lol why would you) but I got one for free after writing an app for it and I really enjoyed their bezel features[1] and always wish my iDevices had the same feature set. These gestures are nothing iOS can't do, but I find they stay out of the way unless you want them unlike some games on apple where you might confuse the app/os on what you want that swipe to do.
Samsung seems to be taking this to a new level
[1] http://playbookwiki.org/index.php/Bezel_Gestures