Why must Nintendo do this to the weak, loyal consumers.
Keep in mind that this
isn't a replacement for the DSi, it's an alternative. For many/most people the LL will simply be too big (it's really big compared to the ordinary DSi).
Also, I think frankly the bigger screen doesn't look as good: besides the bigger and more obvious pixels, the LL displays I saw seemed to flicker in a way that the DSi doesn't (I'm not totally sure exactly what the problem is, but that's the sense I got).
So for someone with bad eyesight, it's a great product, but I don't think it's for everyone.
[Of course, the very fact that Nintendo is worrying about niche audiences like that gives an idea how dominant the DS is...]