First impression: it's a pretty neat little toy. Small enough that it's not a pain in the ass to carry to work with me, for those times I spend sitting in my truck waiting for one thing or another. It's just slightly awkward for me to hang on to; it doesn't seem to fit in my hands very comfortably, but nothing major and after awhile I don't notice it so much when I'm playing. For the most part, though, I don't think I'll be using the stylus a whole lot. I tried playing the Metroid demo setup to use the stylus with my right hand and the directional pad with my left, and boy talk about awkward as hell! I got a little used to it after awhile, but I truly couldn't see spending any significant amount of time playing like that.
Spent a good part of the day playing Mario and getting used to it. It's a little awkward not having analog control for movement (Mario allows you to set it up to use the stylus for analog control, but see above for why I don't like that...) but after awhile you get used to it and it's not so bad. I like the changes that they've added onto the game, on top of what it was for the N64-- the ability to play as Yoshi, Mario, Luigi or Wario, the various abilities that each has, etc... I actually have only managed to rescue Mario so far (you start the game as Yoshi and have to find keys to unlock the others).
Next, I'm going to have to look into the selection of RPG and adventure style games available for the DS, or coming soon. I'm aware that it will play GBA games, so I'll probably end up picking up older games (anything Zelda, etc.), but it would be nice to find some good ones made specifically for the DS. And action games such as Metroid are probably going to forever be beyond me, given my level of suckitude with the stylus. [grin]