God, now I really want this thing! I don't care if it is $300, the things is a pocket-sized beast. Ocarina of Time 3D, Metal Gear Solid 3, and Kid Icarus Uprising look amazing, and I'm glad with what they did with the interface in Ocarina of Time 3D. I also like the inclusion of Miis and how you can just take a picture of someone, and it automatically makes a Mii out of it. The inclusion of the feature to pause the game and do something else is also cool as well.
Backwards compatibility is to be expected, since the DS cartridge and the 3DS cartridge are the same thing, with the exception of a small tab on the 3DS cartridge that prevents it from being placed in a DS. The, what I call, "Virtual Portable Console" sounds awesome as well. Perhaps the games can be rendered at a higher resolution, support 3DS-3DS multiplayer to mimic link-cables, etc. Perhaps it can allow me to not have to try to hunt down every GameBoy game that I still need to buy.
So, yeah, in short, ME WANT 3DS!!!
How about "Virtual Handheld"? That sounds much better!
I also heard you can transfer your DSi Shop downloads over to the 3DS (Then this means that whenever the Wii's successor comes out, we'll be able to transfer our Virtual Console and WiiWare !!)