Cablevision's Optimum Voice VoIP service is now at 250,000 subscribers, making them clearly the number two to Vonage and the runaway leader within the MSO's when it comes to telephony services that are SIP based.
But unlike CallVantage, VoicePulse, Vonage, Packet8, Broadvoice or any of the other telephone adapter driven competitors, you can't go to another broadband enabled location and take your VoIP with you.
That is one *MAJOR* differentiator between the offerings from the MSO's and the Next Generation players.