Apparently there is, already, a "second generation" of the original WDTV HD. It appears that it supports DTS down-sampling. But is not really clear what is difference, from hardware perspective, with the first generation as the DTS down-sampling is a matter of firmware.
There is a new firmware line for it, too. Probably is the WDTV Live with its net features cut, that helps the production.
For the first generation we haven't much to expect any more. Any way it works for me, except that in the latest version is not working the "play one after another" when you press "Play". But I can go to a previous version as I didn't see any much difference for the files I play.