I've been looking, but it would be nice if I could get a bit more meat on the setting than is in the few sourcebooks I've seen.  Just curious if they have some story fluff hidden somewhere?

There's a two-part comic about Dust that gives a little bit of background. It should be available through a comics retailer. Also, there are some sourcebooks (sketchbooks) available through the Parente's Dust site.

There is a lot of the background in the rule books, but also look for Dust Chronicles issues, the Dust Modelling magazine (there is 1 issue in english and 1 in japanese), the Dust Sourcebook and the Dust Wars and Dust comics book series as mentioned above. Look at the Dust Models website for most of that stuff as well as Dust-Chronicles.com or whatever its link is.

Once again I put forward that we need a Dust RPG, one of the big reasons for which being the mass of background material that would be revealed!

Have you seen the new Star Wars RPG and tacticle game?  Looks like they're already experimenting with the idea of cross-genre gaming.  I think we could easilly see an RPG based on dust in the next year, if interest picks up for the tactics/warfare game.