Social software enables people to rendezvous, connect or collaborate through computer-mediated communication and to form online communities. (from Wikipedia)
To learn more about what Social Software is (or is not), or to engage in discussion about its nature, try:
While the term Social Software simply refers to a category of software, its unique importance is as a technology phenomenon. By leveraging the interconnectness of people and their individual participation in value production, this phenomenon highlights several significant shifts in how software works and may be used.
This phenomenon has played an important role in inspiring the belief that problems can be solved better collectively and that online technology can play a critical role.