DH is planning on getting DD a DSi for her birthday this year (she'll be 4). He wants to get her that one because you can take pictures (and sound) with it and then you can manipulate them - add color, funny faces, etc. I secretly want a DS for myself so I'm all for him getting it.
Re: What age for a DS?
hahahaaa!!! I would have been totally confused too, but I saw your other post.
I would say age... 7? but i'm really not sure about those things, I don't know much about them.