There is now report on Twitter that Facebook/Twitter access has been restored, and that Gaddafi's son is preparing a press conference in Tripoli. The Libyan Interior Minister has resigned, defected and joined the protests. There are also reports that an entire army battalion in Misurata have defected and joined the protesters also, and the tribes are trying to rally round and organise themselves.
If all this is true, then I consider it likely that the noose is tightening and the net closing in. Possibly another Ceaucescu moment, as I said earlier.