My goodness, that “case-by-case” statement suggests a nightmare for Google. If they don’t abandon it, the amount of ads on everything except a few terms is likely to remain the same.
On the other hand… they could be trying to have their cake and eat it too. Stop taking ads for an “online casino” search, but allow booksellers and “stalking horse” sites (like partypoker.net) to advertise on most everything else.