- Charger Stand and adapter,
- Longer, extending stylus (10 cm compared to DS Lite's 8.5 cm),
- 2GB SD card,
- Game Boy and GB Color Virtual Console,
- Plays DS games,
- 3 cameras, two outside and one inside,
- Top screen: 3.53 inches, 800x240,
- Bottom screen: 3.02 inches, 320x240
Perhaps the biggest news here is the new Virtual Console feature. Game Boy and Game Boy Color games are going to be available, meaning Nintendo will be re-releasing many classic games for the first time. Only Super Mario Land and Link's Awakening DX have been announced so far, but those two are a great start. I'm sure Metroid II will be on the service pretty quickly, since it's never been revisited since the Game Boy.
Perhaps down the line Nintendo will also add Game Gear titles if Sega gets on board with this. The DS should be more than capable of running those. IIRC, the Game Gear was also capable of running Master System games, so who knows, we might even get classic Phantasy Star on the 3DS at some point.