Maps would have to be ad-based to be viable. The question is if it would be viable without feeding to/from the rest of Google's ad business, or if it would hav

Maps would have to be ad-based to be viable. The question is if it would be viable without feeding to/from the rest of Google's ad business, or if it would have to resort to Yelp-style thinly disguised extortion to survive. "Nice restaurant you got there, it'd be a real shame if it fell to page 17 in the listings and all the one-star reviews were listed first. Did you know you can delete negative reviews and get guaranteed first page if you buy the Premium package?"