I sent this to them a while ago and got back... the canned reply :-)
Dear Mr. Cablevision,
Thank you for providing me with 16 1/2 High Definition cable channels.
High definition channels are important to me in helping me determine which provider to fork over my cash to. Although I would like to subscribe to every HDTV provider that is available, due to a limited number of dollars at my disposal, I cannot always accommodate every company. I do my best, however, to provide my money to the provider that has the widest range of HD channels.
While I do make every attempt to accommodate HDTV providers, factors such as no VOOM HD channels, no Discovery HD, no INHD2, no TNT-HD and pronounced income limitations, may limit my ability to subscribe to every provider available.
While Cablevision - Brooklyn - iO Digital Service may continue to be my HDTV provider at this time, there is a distinct possibility it may be dropped in the future.
Again, thank you for your interest in having me as an HD customer and thank you for YES-HD,
Cablevision HD Customer