16. The computer program product of claim 12 , wherein interest score is generated by multiplying the reply score and the affinity.
12. The computer program product of claim 11 , wherein calculating an interest score for a reply from the plurality of replies comprises: determining a reply score for the reply, the reply score representing a popularity of the reply among users of the social networking system; determining an affinity between the requesting user and a user associated with the reply; and generating the interest score for the reply based on the reply score and the affinity.