A social network appreciation platform (SNAP) for marketing products or services of a merchant to customers online. A server receives marketing campaigns, announcements, coupons, or other messages defined by a participating merchant, for distribution to certain social networks to which a customer of the merchant belongs. The server also receives registration information from the customer including a unique identifier for use in purchase transactions, a selection of the customer's social networks to which certain of the merchant-defined messages are to be distributed, and a selection of the messages for distribution to the selected social networks. In response to transaction data from a transaction source representing a customer purchase, including the customer's unique identifier, the server transmits the messages selected by the customer to each social network selected by the customer, for display on the customer's page and viewing by friends or followers of the customer on the network.