If jailbreakers can do it, Apple can do it, and I hardly see how having a "jump to bottom of screen" would be a security or stability hole.

There are a lot of things Apple could do but won't because their UI designers have blind spots and on top of it have the architect "don't harsh My Great Vision" thing going on. For me, the "killer app" for jailbreaking (and which I no longer have to worry about because Android's got it built in) was quick access to settings via the "menubar".