My guess is that they will keep both services going since the "other" guys will be most likely unable to carry the new HD service. Was my impression that Discovery HD and Bravo HD were in the Marquee Plus Pak---
Turner Broadcasting System will launch a high-definition version of Turner Network Television (TNT) in May. The new network, TNT HD, will feature the channel's mix of off-net series, theatrical movies, sports and originals.
TNT HD will debut with the National Basketball Association Western Conference Finals in HD (1080i). It will feature a mix of true HD content, including NBA and NASCAR events and originals, while other programming, will be upconverted from standard definition.
TNT plans to make its original shows in HD, beginning with the terrorism drama The Grid, a series slated to debut this summer.
For production, the network recently purchased a full complement of Fujinon HD ENG-style lenses to shoot program elements and has outfitted its new HD truck with Ikegami HD cameras for a variety of sports and other programs.
I just called and the sales rep hadn't heard anything about TNT HD. She did give me the prototypical "when it becomes available we will prolly start negotiations" So I laughed at her and said kinda like those ESPN Negotiations and she didn't think it was too funny.