HBO executives have been hashing out the details of what they will offer online, and a spokesman says no formal decision has been made. But programming will almost certainly be offered via a subscription service, much like the mixture of HBO movies and original fare such as The Wire, Deadwood, and Big Love now offered by cable and satellite operators for a monthly fee of $10 to $12 or more.

There may also be features that let users download HBO programming to other devices. HBO now provides full-length episodes of programs such as Entourage and Sex and the City to customers of AT&T's Cingular Wireless for $4.99 a month, but this would be the channel's first move onto the Web.

Where a new HBO service gets sticky-and why it has taken so long to put together-is that a new broadband offering would put HBO into competition with the cable and satellite operators that now pay the bulk of the estimated $3.5 billion a year in revenues HBO generates. Those "affiliates" generally pay HBO around $6 a month for each of its nearly 30 million subscribers, according to cable industry analyst Kagan Research. The arrangement generated $863 million in cash flow last year.