Channel 100 will provide access to the "showcase" application that puts on one screen the five NBC Universal cable networks carrying the Olympics (MSNBC, CNBC, USA, Bravo, and Telemundo) plus the highlights channel (Channel 147). The only live coverage on Channel 100 will be whatever's on one of the cable networks.
All the cable networks (including Telemundo) will be freeview during the Olympics; every E* customer will have access to all of them, even if they can't get the interactive application.