I don't know how desired button remapping is for people, I want it badly for Halo, but let's hope that Sony doing it has put some pressure on MS to do it. They don't need to do any game level changing, if you remapped a button you should know what it replaced, simple as that.
As for functionality, I'd really like a guide again, but I don't think snap will ever leave due to the fact that games change states for snap (change resolution & other graphical effects). What should really happen is that a single tap brings up a guide (from which you can go to the home screen), double tap brings up snap as always, and hold works as normal.