I must confess I went and set "Yes" which seemed natural from a cursory glance, and because it was the opposite to the default setting, then I read CG's comment in a different thread from the one that I first saw the new option, that he'd already set 1000+ users.
When I went back and checked, I read more carefully and realized my mistake, so I have to agree with Mak that there's plenty of scope for confusion with the current wording.
I don't think you'd place much reliance on the result of a poll which asked, "Are you in favour of nuclear disarmament, or should we keep the bomb ? Reply Yes or No.
Mak and I are proof that people can't be relied upon always to read with great care. Not that it's of great consequence. It should be pretty obvious that you've ticked the wrong box when the ads don't go away.