the iOS/adroid facebook app has "peek" that swipe to the left. lots of android apps have it too espefially thise following the holo design philosophy. BB10 is the culmination of every type of UX we've ever known, taken to a whole new level. Out of the box elegance really means, that they've brought back buttons, hidden panels swipe down menues, tabs anx all ghe other user interface paradigms under one hood and manage them all via gestures.
this is done to make the UI obvious to users. it will be "new" but at the same time very familiar
