Following a series of delays, Cablevision Systems Corp. launched its highly-anticipated digital service in late September, offering it to about 500,000 subscribers in Western Long Island, N.Y.

The service, dubbed "iO: Interactive Optimum," offers a suite of advanced applications such as video-on-demand, subscription-VOD, interactive television, an expanded video lineup, 45 channels of commercial-free digital music, e-mail and a customizable program guide.

Using relatively thick Sony Corp. digital boxes with embedded DOCSIS-based cable modems, Cablevision's iTV offering includes news, weather and lifestyle content from its Rainbow Media Holdings division, as well as an image storage service called "PhotoNetTV," which allows subscribers to create photo slideshows that can be viewed and retrieved via their televisions, and "Playjam," which offers a variety of basic games.

Cablevision said digital installations began on Sept. 28 in Western Long Island, including Nassau County and some areas of Suffolk County. The MSO is offering the complete iO package for $29.95 per month, or $19.95 per month for the first year of service if customers sign on before the end of this year. On top of that, iO customers will pay $5.95 per month for each digital box.

Cablevision executives have said the company plans to explore future set-tops with on-board PVR capabilities, and has studied the virtues of sidecar PVRs, which would plug-in and sync with digital set-tops that do not have embedded hard drives for video storage.