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Concentrating on these verticals is critical to aggregating local advertisers.
The one industry I find that goes outside that mold is Auto Dealers. People will travel far and wide for the best deal so the dealers are willing to spend the money on the ads for a very large target area.
The Home Improvement or Home Repairs (Plumbers, A/C, etc) Industries seem to be the ones catching on the quickest from what I am seeing.