I've said it once and I'll say it million times more if need be; NO!! This isn't a god damn PSP2, it's just a redesign of the PSP, hence forth a second nub is neither practical or a good idea in general to implement. It would just be redundant. It would server no use, nor be usable for early games as that means patching every single god damn game, which would be a disastrous failure. If used in future games it would fuck over anyone who DOESN'T have a Go and not everyone is willing to upgrade to this.
Also NO, I know what your thinking right now, your going to point to the PS1 and it's transition to the dual shock as your defense. Well guess what, NO that will not work in this case at all for all the reasons I have said and one critical one. Unlike the PSP's console brothers, it's control mechanism is built into the system and cannot be switch. With the PS1 you were able to just buy a new controller and poof, all games there on wouldn't be a hassle. Hand Helds do not have that luxury, so for the millionth time NO! Dual analogue is something that is best left for the PSP2 (whenever that comes out).