14. The method of claim 10 , wherein the activity associated with the listing is associated with an activity constant that is used to update the user reputation score.
10. A method comprising: receiving a request, over a network at a social shopping platform, from a user in a first community of users, the social shopping platform including a plurality of network-based marketplaces respectively associated with a plurality of communities, the plurality of communities including the first community of users that is associated with a first network-based marketplace; identifying the first network-based marketplace from the plurality of network-based marketplaces based on the request, the request for an activity associated with a listing for sale in the first network-based marketplace that is used by the first community of users to transact listings that describe items of a single domain that is of interest to the first community of users; updating a listing reputation score for the listing based on a user reputation score for the user and based upon the activity associated with the listing; and updating the user reputation score based on the listing reputation score.