First, why do people continually fail to acknowledge that there is no reason we can't have both perks AND attributes, like in Oblivion!
Because it's not going to happen. Why should we debate what's already been placed out of the scope of possibility?
Second, seeing as though all we've really heard about this is pure PR from Todd, we can only rely on past history to try and guess whether perks add more depth. Well, past history is 100% clear on the subject of depth in TES games. It gets smaller over time.
Actually, what TES has been losing every game is breadth, not depth. Every game clearly limits the range of all possible activities of the last, as opposed to the limits one can take a single activity.