You need HDMI 1.3b (most things so far are 1.3a, so no dice) to transport the raw TruHD or DD+ streams to an external decoder (i.e. AV receiver). However, since this is totally useless in advanced mode discs (nearly all HD-DVDs) because the menu sounds and commentary tracks need to be mixed in, this doesn't matter.
All you really need is HDMI (1.1? 1.2? I can't remember) that can carry 5.1 or more LPCM, and a receiver that supports said format.
UNFORTUNATELY they didn't redesign the audio portion of the Elite from the previous models, just hooked the existing digital out circuitry to the HDMI chip so all you can get out of it is the same thing as toslink - DD up to 640kbps, DTS up to 1.5mbps, and WMA Pro up to 1.5mbps.
Having said that, already the (night mode afflicted) DD+ transcoded to DD sounded amazing, so I imagine having night mode disabled and going into DTS or WMA Pro (if you have a Pioneer receiver that handles it) will rock your face off. Most of you probably don't even have sound systems capable of noticing the difference at that point.
Hopefully a later revision will bring true LPCM surround to the product lineup. Probably about the same time someone releases a HDMI video card with actual 5.1 / 7.1 LPCM audio output (not this silly toslink pass thru, even the new ATIs are effectively the same, only bonus being the stereo / DD/DTS pass thru sound 'card' is built in).