http://www.anandtech.com/audio/showdoc.html?i=2079
Brief coverage of the emerging audio formats including DVD-A, SACD and Intel's about-to-be-released Azalia. The article focuses mostly on comparing the amount of bandwidth available in each format
Most interesting to me were the last 2 paragraphs discussing Azalia--which Intel is now calling Intel High Definition Audio. This is debuting this year (officially next week) as Intel's replacement for AC97.