We are all speculating at this point. We only know these facts from Famitsu:
Originally Posted by Cosmonaut X
(speculating here in the case of MGS3)
I understand the strict "well, there's nothing official to say this is more than a simple peripheral" line, but I think it would be obtuse not to look at this announcement, the delay of certain titles, the apparently-solid rumours (on this at least) from 01Net and see that this will likely be more significant than that.
It is *currently* a peripheral for monster hunter. Much as with other plastic addons it may be used for other games, or it may not be. Monster Hunter will be playable without it. You can play Xenoblade with the classic controller, and it ships with one - but it plays perfectly fine with the default Wiimote+Nunchuck combo as well. I'll gladly eat my crow if Nintendo announces next week that the 3DS is being abandoned in favour of the 3DDAS XL. I just think this is overreaction on most people's parts.