In iOS 7 there are many more gestures that will activate functionality from the lock screen. In addition to swiping up and down, the main side swipe is far easier to execute. For example you can drag a steeper diagonals and the starting point can be anywhere on the screen.
If a lock screens purpose is to prevent accidental input, then the iOS 7 implementation fails.
I always thought that the "slide along a path" that iOS 1 implemented was brilliant. It addressed a real issue in a seamless and nearly fool proof maner. As you begin adding more to functionally to the lock screen, the design gets further away from its purpose. Honestly if you want to add that much functionality to the lock screen, just get rid of it. Lock screens are turning into a second Homescreen.