Intervideo has announced that WinDVD HD is the first software HD DVD player to feature support for Dolby TrueHD and Dolby Digital Plus. Here's part of their press release:
InterVideo, Inc. (Nasdaq:IVII - News), a leading provider of integrated digital and high-definition multimedia and audio/video content solutions in the PC, CE and wireless industries, today announced that its WinDVD HD(TM) is the first software HD DVD disc player to include Dolby TrueHD and Dolby Digital Plus technologies for high-definition audio.

Both Dolby TrueHD and Dolby Digital Plus are surround sound audio codecs developed by Dolby Laboratories, Inc. (NYSE:DLB - News) as the next-generation audio technologies for high-definition programming and media. Dolby TrueHD delivers tantalizing sound and offers an unprecedented home theater experience. Dolby Digital Plus combines the efficiency to meet future broadcast demands with the power and flexibility to realize the full audio potential of HD DVD discs for an amazing high-definition experience.
If you'd like to read more, Intervideo's entire press release can be found here.