I'd have to agree with you that gesture interactions tend to feel more natural then typical button pressing (e.g. pinch-to-zoom), but can be a little awkward for first time users. A customer who stops by a mobile phone kiosk while walking through their local mall might not know how to handle a BB10 device without assistance from a sales associate. However, gestures often become second-nature, and users rarely find themselves asking "how do I do this again?"

Swipe-upwards to unlock/return to homescreen requires initial contact with the screen's bezel, which should mitigate the number of times this gesture is unnecessarily actuated.