Yeah, latest word is no b/c they're gonna work on another bracket first. That's from Cobb's product update on m3f.
Maybe dabears will make some progress on a box for the Nano after he gets his orders filled. He promised to do some testing on a prototype but no news yet. One thing about the Cobb box if it comes to fruition is that their MAF has a mounting point built into it already as you can see here with this fabbed up heat shield:
http://i55.photobucket.com/albums/g138/fairxchild/personal/IMG_2452.jpg
To pile hypothetical upon hypothetical, I'm wondering how much trouble it will be to adapt their sealed box to the Nano in a way that keeps the seal. If it doesn't we're probably just as well off fabbing a heat shield similar to the one on K&N's SRI.