i never noticed seeing video cards going on sale on black friday's.
i think a lot of the items that go on sale during black friday's are more consumer products like tv's, monitor's, external harddrives, mouse, keyboards, etc.
i think you should be able to get the graphics cards with no worries for now, but dont get discouraged when you see the gpu you got is a lot cheaper few months from now, its just how it always is.
if you need the gpu upgrade, then dont wait. just get it!