The other day I noted that the Judgment Day ad on our corner had disappeared.
But I keep seeing the ads on BART cars, so it's not as if they've vanished altogether. (Though it has been noted that BART doesn't have a great track record for replacing out-of-date ads. I'm pretty sure there's a few "Step Up 3-D" posters around.)
Maybe when the Rapture comes on the 21st, all the ads will be spirited away to heaven. One can hope.