John Battelle, Greg Sterling and Garrett French have written critiques of merchant Circle, a new free listings tool for small businesses. Garrett was the first to highlight the social networking viral aspect of the service where individual merchants can list other local businesses in which they are affiliated. Here's an example. Here's what Garrett has to say about it:

Yahoo Local Listings Crushed by Merchant Circle Social Network
So what I think MerchantCircle offers that's going to crush Yahoo (and the YPs too, though I'll leave discussion of *that* industry to my esteemed colleagues) is the local business owner social network.

Because when local business owners invite others into their local networks they can put ads on *their* pages (sort of like comments in MySpace). In addition, a given local business page's site will also include all of that person's contacts within the local business community, giving their associates a little cross-linking boost and emphasizing their connections.

MerchantCircle makes it profitable (from a presence perspective) for business owners to invite other business owners into the fold - it becomes a sort of popularity game the way that MySpace is, which will drive their viral spread over Yahoo.

In fact, I think it will drive their viral spread even before MerchantCircle users start to notice an actual measurable return (through the redemption of coupons).