Kind of odd, but yes , from inside looking out in particular , the no-see-um mesh can look transparent.
I shot this quick video mostly to show a low pitch, but you can probably get a better feel of what the shelter is really like. Note that the mesh can look from black to totally clear as the camera pans around.
http://www.youtube.com/watch?v=Gv8Mxbpc1ac&feature=channel
Franco

Bit of trivia.
In theatre productions that "now you see it now you don't" effect is done with a sharktooth scrim, not that different from mesh netting. Depending where you light it from it is totally opaque or clear.
It is used to hide part of the stage to allow a new scene to be put into place and stuff like that.