1. A method of processing messages, comprising: at a computer system having one or more processors and memory storing one or more programs executed by the one or more processors: receiving a plurality of messages directed to a particular user; determining a respective conversation for each of the plurality of messages; sending to a client system for display, a first list of conversations including the respective conversation, as a set of rows, each row corresponding to one of the listed conversations and including at least a sender list configured by the computer system to include only identifiers of senders of messages in the conversation corresponding to the row; enabling the particular user to identify one or more conversations in the first list of conversations, and to mark the identified one or more conversations as belonging to a particular category while continuing to display at least a portion of the first list of conversations, which includes the identified one or more conversations; and sending to the client system for display a second list of conversations, the second list comprising only conversations marked as belonging to the particular category.
1. A method of processing messages, comprising: at a computer system having one or more processors and memory storing one or more programs executed by the one or more processors: receiving a plurality of messages directed to a particular user; determining a respective conversation for each of the plurality of messages; sending to a client system for display, a first list of conversations including the respective conversation, as a set of rows, each row corresponding to one of the listed conversations and including at least a sender list configured by the computer system to include only identifiers of senders of messages in the conversation corresponding to the row; enabling the particular user to identify one or more conversations in the first list of conversations, and to mark the identified one or more conversations as belonging to a particular category while continuing to display at least a portion of the first list of conversations, which includes the identified one or more conversations; and sending to the client system for display a second list of conversations, the second list comprising only conversations marked as belonging to the particular category. 6. The method of claim 1 , including sending to the client system for display content of a respective user-selected conversation when the user selects the respective conversation in the first list of conversations.