SiliconBeat has some good thoughts on it:
…MerchantCircle has pre-populated its database with generic business listings. Business owners can then sign in to claim their profile pages.
…Smith doesn’t view MerchantCircle as a destination site for users. Most people won’t go here looking for a local bike shop, although you could. Instead, they’ll find MerchantCircle profiles when they’re Googling for Palo Alto bike shops, for example.
The “circle” in the company’s name comes from the idea that merchants will create networks of affiliated businesses by adding their names to their profile pages and swapping ads with each other. The idea is to give merchants an incentive to invite other merchants into MerchantCircle. Indeed, Smith is relying on this type of viral marketing to build his business because he doesn’t have a cadre of salespeople to recruit business owners.
Garrett French has more on MerchantCircle here, as does Greg Sterling.