I bought some digital camo fabric over the weekend too, and it was unmarked as to material. It feels like the same weight and texture/slickness as rip-stop nylon, but I wasn't sure what it was. I wonder if it's the same stuff y'all are talking about here.
Let me ask: does the fabric you're talking about have rectangular 'grids' that look like rip-stop nylon but slightly smaller? How wide is the bolt from selvedge to selvedge? Mine measures 62". And it only has the camo pattern on one side. The other side is not colored, but you can see the camo pattern through it.
I weighed it on my kitchen scale. It comes out to something like 2.16 ounces per square yard (assuming they gave me exactly 4 linear yards of material, although I usually get a bit more than what I'm paying for). I was assuming that this is 1.9-oz rip-stop. Am I wrong?