$170.
OK, first a complaint

They made it a little wider and thinner. This requires that all those nerf armors and stuff like that be replaced.
They changed the shape of the charger plug. Although the power requirements are the same. How do I know that? The car charger has one cord out,t hen it splits - into one for the DS and DSi. So again, pure marketing ploy.
SCREW YOU NINTENDO! you could have left it the same size and plug shape, but NOOOO you had to be money hungry weasels who should be shot with rockshalt shotguns!
Anyhow..
Only comes in black and light blue.
No longer has the slot ofr the old gameboy games.
Has a Slot for SD memory card.
Slightly larger screens. T hey say it is brighter, but not sure.
Has 2 cameras. One on inside so you can see it while open, one on outside. Not really sure why you have it on the outside, because when you try to use it, you can't see what it is aimed at, but I suppose that is true of the inside camera (if it isn't aimed at you).
YOu can download new games/content online. Only like 5 games so far, and IMO they all suck. Gonna wait. It comes with 1000 free points (about $10 value, I think) when you buy it for now.
I only "upgraded' because
a) my old DS was starting to get a bit worn and seemed to not always like charging.
b) I got $70 trade in towards the DSi for it.
c) I already had $100 credit by trading in old games.
Boom.. new DSi for "free"
I actually connected to my wi-fi with the DSi. Never bothered with teh DS. It seems ok. INternet is a bit slow, but what do you expect.
SO far, no complaints other then that nintendo is full of excrement for deliberately changing it to make old add-ons useless.
I'll add more if I ever download stuff other than the free browser.
The games available for download:
frog that grabs beans from air with tongue
some puzzle game to get diver down to bottom of ocean?
game that you look at yourself in camera and move to look like on roller coaster and stuff.
that sort of junk.
Hopefully some good games will eventually be available.