I think the DS is incredibly nifty.
You don't use the stylus to "move her around." You use the directional pad. The touch screen is for looking, aiming, jumping, changing gun modes, switching to morph ball mode, and looking at the map. You can also use the thumbstrap thingy to use your thumb (or a different finger) in place of the stylus.
I currently don't have a DS... the price is kinda steep and I MAY keep this RAM I bought for HL2 (actually they'll be releasing a patch soon for this certain problem so I will probably not need the extra RAM), and I also have my eyes set on Metal Gear Solid 3. I don't play my handhelds much... but hey, if EB or Gamestop has some trade-in thing... who knows.
And btw, the wireless thing is great. LoL, you won't believe how many cheap bastards there are like me who don't want to buy a link cable.
But yeah, right now the games don't look TOO impressive (graphically) to me. I just kinda feel like I'm playing a PS game on a handheld or something.
Well, actually, Super Mario 64 DS is supposed to be better-looking and higher-poly than the original one...
EDIT: Also, if you just ignore the dual screens, the microphone, the touch screen stuff, the backlit screens, etc., you have the "it's like a portable N64" feature left. ... I loved the Nintendo 64.