Ok, a lot of this thread is pretty stupid (but then a certain poster has a lot of posts in it, so that explains that one), but for the...oh I don't know...20th time, the DS couldn't have had only one analogue stick.
The DS has a symmetrical design for a reason: the stylus/touchscreen. You don't want to be using the stylus with your weaker hand (especially not on games which require a lot of precision), so the buttons mirror the D-pad. So now developers just have to put in a quick switch in the menu options so the D-pad and L button controls switch to the face buttons and R button controls (this of course only applies to games which use both sorts of controls, MP: Hunters for example). So, if Nintendo were to add an analogue stick, they'd have to add one on the other side.
Now I'm not saying Nintendo should have put two on, I think they should have (though if the thumpad controls work out fine as an imitation analogue stick, i don't much care either way). But maybe it was dropped for a cost issue...I honestly don't know how much it would cost, but you know how Nintendo don't like to eat up the cost on systems. We already know they dropped motion sensor control from the DS for that reason (and I'm absolutely certain that will be one of Revolution's control method's for that reason).
Actually, having said that I think they should have added an analogue stick, maybe I don't. It might have been a smart decision for getting games on the console and attracting consumers, but if the lack somehow extends the lifespan of 2D games, I'm all for it.