They should still stay true to their own HIG's, and allow appointments to be made (calendar entries) by tapping the time, as opposed to a "+".
I know! It frustrates me so much that I can't simply tap on a time then drag down to where it ends. That's basically what I do with iCal, click on a time, drag down, and name it, one would think that with a touch interface that's just what we'd do.