I'm sure Nindendo will update the 3DS at some point, and add the extra stick/nub. If they don't, I'm hoping Nyko or someone else will make an attachment with a battery built in, so I can have a second analog along with good battery life, until then, I'll just play the waiting game.
I doubt they will - people kept saying that the GBA would be revised to add two extra face-buttons, and the press claimed that the DS would be dropped for a "GBA 2", too, for example. Those were even more persistent claims, and equally illogical*, and those never happened, either.
*With the 3DS, just as with the other two, this would break compatibility, and is at odds with the fact that the Circle Pad Pro is a niche add-on, for a few niche games, and accordingly is only available in small production numbers in very particular niche retail outlets. If it was of any importance, it would be available everywhere. The niche nature of the games and audience for the add-on makes it unlikely that it ever will be.
Also: Yay! Dillon's Rolling Western is out today!