I was sort of curious about this too as I just bought a NR (got my confirmation it was shipped just a few mins ago). It's synthetic so I would expect it to be a bit larger than a down UQ. It comes with a stuff sack but I believe that is just for storage (there is a photo in one of teh threads)... Think someone said in one of the threads below they are able to get it down to a 8x8 compression sack. However I think i'm just gonna do what the others suggest and just stuff it in the bottom of my pack w/o a sack.
These might help some...
"Only two things are infinite, the universe and human stupidity, and I'm not sure about the former."
- Albert Einstein