hm, probably not the right term for it, but the workspace display in the pager does not show empty workspaces. so if I have windows open in workspaces 1, 3 and 7 e.g. they would be indistinguishable from windows open in workspaces 1, 2 and 3. xmonad does this right, it has all available workspaces displayed in the pager at all times.