No matter what seeting I pick for the "Amount of graoundcover" slider, everything looks the same.  I presume this is supposed to effect how the terrain looks in the 3D map, but there is no difference between my choosing "none", choosing "overgrown (10x)" or anything in between.  It all looks like it normally does (which I presume was "normal" setting, which is what I've left it on in the past).

I haven't played with this option before the current beta, so I can't say if it worked properly in the past.