I downloaded them, but it seems kind of a poor way to do this. Maybe have a preview channel and have multiple sections within it like the nintendo channel but only videogame trailers

Or..maybe..just maybe...use the nintendo video channel? Update it to support more files or something.

Or the eShop, which basically already does this for all other games. I assume they're doing this for the SpotPass feature and the eShop isn't set up to specifiy specific game notices.

The Kid Icarus trailer isn't available on the eShop in North America, or at least I don't see it.

I'm glad it isn't through the Nintendo video channel, because I want to keep these vids.  I still have most of the ones from E3.  I deleted some of those as the games became available, but I kind of wish I had saved them for the sake of posterity.  I'm keeping these!

I do wish there was a way to clean up the 3DS main screen, though.  If I could make a Games folder and a Video folder, that would be great.

I, for one, enjoy the massive cluster of icons I have. As long as they keep increasing the number of slots (they've already done it once) I'll probably keep it that way. Folders would be a nice addition for people who want them, though.

In lieu of folders, I just physically separate my icons as I see fit.  3DS internal software on the left, followed by eShop software and DSiWare, then a blank column and the Ambassador games, then some more blank columns and the downloadable trailers.  I'll probably go through later and add some space between the internal software, eShop software and DSiWare.  They're in order, but they're all lumped together right now.

OCD?  Perhaps...

@Tansunn That's pretty much exactly what I've done. Might be weird, but I find great pleasure in organizing and moving around my icons. That's one reason I like the UI better for both Wii and 3DS over other systems (well, I'm comparing both to the 360 I guess) which is just a list of names. Aside from all the other ads and stuff. Blech.
Another possible OCD tendency: My comment that these "trailers" are but gameplay vids, at least the ones I've seen so far. Like the bit of art on the icon, but like the E3 videos much better so far.
And when can we get another Nintendo 3D show? I enjoyed her, I mean it.