Any guesses what will be covered beyond firmware updates and holiday titles? Software announcements are always good, and I'm still eagerly waiting for any information about Flipnote Memo (although have no reason to expect it here).

I'll bet you it will be 3D Video Capture.  I hope when they make a revision they put in some better cameras.  3D pictures are cool but they need better resolution.

Some Mario Kart 7 online details would be nice

Agreed about the revision. Existing cameras are so poor that they aren't worth using for regular photos or videos. Trying to create 3D content is going to make that quality issue even more noticable.

God, the cameras are pretty terrible. I honestly think if Nintendo bumped it up to something like 2 megapixels or something, it can be a hell of a lot better. My family had a digital camera that took floppy disks back about 12 years ago, and it seems like it took better quality pictures than what the DSi/3DS gives us. Ugh! I could go on forever about this!

I'm gonna guess that this conference will also showcase the analog slider attachment and maybe give us names and dates for the free GBA games we are waiting on.