From what I can tell, I along with many others hold the opinion that having a designated "jump button" that you could use at any time in this game would be rather obnoxious. However, a jump feature would certainly have uses, like getting over that small cliff that's slightly too big to walk over. Therefore, why not implement a system like the one used in FFXIII, where there are certain locations where you are prompted to jump, and you can only use the jump feature in these locations? Personally, I think that would be really cool.