According To Multichannel.com:

Time Warner Cable confirmed Monday it will stop offering HDNet and HDNet Movies across all of its systems effective May 31.

The move by Time Warner Cable, which has 8.7 million digital cable subscribers, is a blow to the Mark Cuban-backed HDNet, which was among the first HD services available to cable and satellite operators.

Asked why the company was dropping HDNet's services, Time Warner Cable director of corporate public relations Robyn Watson said, "There's a limited appeal for the programming. In a world with more than 100 HD channels, being in HD is not enough. We are adding other channels in HD to give our customers more choice."

HDNet and HDNet Movies has been available to Time Warner Cable customers in the HD Xtra premium-priced tier, which depending on market costs up to $8.95 extra per month.

Cuban, in an e-mail to Multichannel News, said he would not comment "on ongoing negotiations." However, he took issue with Time Warner Cable's characterization of HDNet's programming as lacking appeal.

"[T]here are millions of viewers who enjoy our unique and exclusive programming," Cuban wrote, adding that "we are not a cookie-cutter network like those from the big media conglomerates" and claiming that HDNet's viewers "do business with providers specifically to get our progamming."

HDNet's flagship channel, launched in 2001, features up to 20 hours per week of original features, including a newsmagazine hosted by former CBS anchor Dan Rather.

Time Warner Cable disclosed the plans to drop the two HDNet services on its Web site May 15. The company also said on or about June 1 it will launch MAV TV HD, as part of the HD Xtra tier.

In New York City, at least, TWC this month added Smithsonian HD in the HD Xtra tier. In earlier Web site statements about the two HDNet channels, TWC had said it intended to drop them and add Smithsonian HD and MavTV.

Well, according to Mark Cuban they are still negotiating but this can't be good.  I just added HDNet like 3 months ago, and I've really enjoyed access to MMA action I wouldn't be able to see otherwise.  I must say that the only reason I wanted HDNet was for the MMA coverage.  I guess we can forget about being able to watch some of the Japanese MMA promotions as well if this comes to fruition.