HDMI
does carry audio, but what sort of audio it carries depends entirely on which version of HDMI you are talking about - and
that is why Outlaw elected to avoid HDMI connections when they developed the 990. The Model 990 entered production in the spring of 2005, almost six months before HDMI v1.2 was released and about 15 months before v1.3 was released - at the time, v1.1 was a newly released standard (it wasn't even published until May 2004, so integrating parts that supported it would likely have forced them to delay production by several months) and it was already clear to
everybody in the industry knew that revisions to HDMI were in the near future. Those future versions would require different hardware to support (firmware updates alone couldn't make an HDMI v1.1 product become v1.2), and there was a great deal of uncertainty as to when they would appear and how they would work with HD-DVD and Blu-ray. Including HDMI v1.0 would have just been a source of frustration for owners a year down the road because it would offer no more capability than HDMI plus an optical or coaxial digital audio cable - v1.1 was the version that added support for multichannel PCM.
As for getting 1080p video from Blu-ray or HD-DVD players, you can pass that through the 990's DVI switching without any trouble (assuming your display also supports it, of course). Single-link DVI (the form of DVI used as the video side of HDMI) can support resolutions up to 1080p just fine. For audio, you can use either optical/coaxial digital audio or multichannel analog audio.
If you want even more details, you can check out my
HDMI FAQ .