1. A computer system for contact information management, comprising: a communications interface in network communication with a client computer and an addressee computer; and a computer processor that is operatively coupled to the communications interface and programmed to (i) receive from the client computer existing contact information of an addressee extracted from an address book data structure of an address book, (ii) transmit to the addressee computer an update request, wherein the update request is a request for an update to the existing contact information from the addressee computer, wherein the update request is transmitted to the addressee computer in response to the existing contact information being extracted from the address book data structure of the address book, and (iii) subsequent to transmitting the update request to the addressee computer, receive from the addressee computer an update to the existing contact information, wherein the update is provided by the addressee computer in response to the addressee computer receiving the update request.