Nintendo DS has a touchpad, yes? To me that says that there will likely also be a stylus. What pocket size devices do you know of that include a stylus? I'm thinking a sub $200 handheld game machine with PDA functionality. That 1 gigabit they keep talking about is how big a flash rom it will support.
That also supports the third pillar statements, because it would be significantly different from the GBA. Woah.
-bmfrosty