If their games are entincing you, the lack of a second analog shouldn't matter. The games play fine without it. The reason why the Vita (and by extension, the PSP) can't just use one is because Sony keeps trying to make console gaming on their handhelds. You know what's a big thing with consoles? Dual analog sticks. At least Nintendo makes a different experience with their games.
You know that the PSP only had one analog nub, right, and that that nub made for some less-than-comfortable gaming, right? A large part of my decision behind getting a Vita was to play my PSP games with a proper right analog stick for camera control (which has been quite nice, by the way).
The 3DS is getting there with software that interests me, but right now I'm only at 3 designed-for-3DS games that interest me: Castlevania - Lords of Shadow - Mirror of Fate; Resident Evil Revelations (which
does have CPP support); and Kingdom Hearts DDD. The handheld will need more than that before it entices me enough to forget how much I
really disliked playing 3D games with only one nub on the PSP.