I think it's very well-done and well-written, effectively parodying all those innumerable ghost hunting programs. In fact ("as a comedian, in all seriousness," as Bobby Bittman would say), I think it's the funniest thing Jack Black has ever come up with.
Best episodes: "Pilot," "Wrong House," "Hooker with a Heart of Ghoul," "Ghost Writer."
I wish this show had another season...
Anyone else like it? I'm surprised it took me so long to find it.