Here in brazil (at least in são paulo) there are around four companies (groupon included) fighting tooth and nail for this market, even using black-hat-ish techniques (unsolicited email, misguiding website, impossible-to-unsubscribe mailing lists, deceitful ads, etc).
I think most urban-ish places with a capitalized youth are a ripe market for coupon-type businesses.
I think most urban-ish places with a capitalized youth are a ripe market for coupon-type businesses.