I'd love to tell you that the New Xbox Experience HDMI-related sound issue from November has been addressed, but that'd be a lie. More than two months and 23 pages of complaints later, it persists.
To review, when the NXE hit late last year, some Xbox 360 owners who had connected the console to their HDTV using an HDMI cable were greeted with silence. The response from Microsoft at the time was something along the lines of "we're looking into it," while others reported tech support indicated it was an older TV- or hardware-related issue.
Since then, 23 pages of discussion over the issue have sprouted up at the official Xbox forums, and still there has allegedly been no response from customer support. A rumored—a completely unconfirmed rumor—indicates this may be addressed with a February update.
We'd say HDMI and HD gaming are *somewhat* important parts of the Xbox 360 user experience, so we hope that's true, at least for the hundreds of users allegedly without sound for their Xbox 360 games and movies. [Xbox Forums via Boy Genius Report] Update: A fix is coming February 3.