A computer-implemented method of providing invitations to a shared communication space, performed by a server system, includes providing the shared communication space, which includes content associated with a set of characteristics, and identifying a user, in accordance with a set of characteristics associated with the user and the set of characteristics associated with the content in the shared communication space. The method further includes sending to the identified user a invitation to participate in the shared communication space, and upon acceptance of the invitation by the user, enabling access by the user to the shared communication space by the user and enabling the user to exchange information with other participants in the shared communication space via the shared communication space.