I did the same thing. I went over six months with no cable, just signed up about a month ago. I get their entire digital lineup with HBO and Showtime and HD DVR for $45 a month.
If they can offer that as a promo, they can keep it at that price and still make a profit.
Yeah, forgot.. I'm also getting free HBO/Sho for 3 months. They made an offer a couple weeks earlier and I said no go and explained I'm doing Netflix/Hulu/Clearwire. A couple weeks later they came back with a better deal. Still keeping Clearwire unless they can bundle a better deal with cable modem.