I have Cablevision's Optimum Online service at home, and recently I've been having intermittent problems. After some adventures with their automated customer technical support application, I got through to a real live person, who said it was probably my old cable modem. Cablevision would replace it at no charge; all I had to do was go to their walk-in center and I could get a new one.
Interestingly, the new cable modem is a Motorola Surfboard SBV5120 with built-in ATA. [Correction: with eMTA, embedded Media Terminal Adapter; thanks to "VoIP Dude" for the clarification.] I don't subscribe to Optimum Voice (Cablevision's VoIP service). But when talking with another CTS rep later in the day, he mentioned that they're giving out cable modems with eMTAs (though he didn't call them that) to all their customers, so if the customer later decides to buy Optimum Voice, they don't need a cable modem swap.
This tells me a couple things. First, the price differential between the SBV5120 and the SB5100 has to be pretty small. Second, Cablevision has to be expecting a pretty reasonable take rate for Optimum Voice among current Optimum Online customers.