It works, but watch out for frame rate (50/60, not 25/30)!
It is indeed works and works very well. The only issue is to get Compressor 3 and DVD Studio Pro 4. Compressor has the H.264 encoder settings for HD DVD and DVD Studio Pro will be able to import the results. The only issue that a lot of folks are chocked on is to watch out for the Frame Rate. The legal rates for HD-DVD media are: progressive 50fps and 60 fps (not 25/30 some may expect). If you follow the instruction you would notice that author picked 50 fps, but he did not mentioned why.
If you are working with camcoder's HDV source Compressor would select 30 fps by default. If you have DSP v.4.2 - it is not an issue, because of it will perform double frame conversion implicitly, but DSP v.4.1 would just reject the video with "Invalid Format" error, not really very informative. I spent a considerable amount of time, until I found some white papers on apple web site explaining the H.264 rules for DSP.
Also, I found that H.264 1080p/60 encoding is very demanding on CPU and so incredibly slow that you would just give up the whole effort. The playback is also not very smooth even off the HD. But using H.264 720p/60 is ultra fast and very smooth. Another reason for 720p is the fact HDV is really only 1440x900 (or something). This resolution is better suited for full quality 720p, rather then low quality 1080p with a lot missing pixels (it looks quite grainy).
It is shame Apple does not offer any option for Compressor and DVD Studio with FCE or separately. I was lucky to have a Compressor 3 thanks to the Logic Pro Studio. But I ended up getting DVD Studio Pro 4.1 from emule, as there is no other reasonable options.
The SD DVD disks authored in HD-DVD format play nicely on Toshiba HD DVD stand alone players (it detects them as HDDVD) and any Mac or may be PC (with proper hardware and software player). I tried HD disk on XP - and it would not even show the content of the disk.
Finally, I could resume making HD family movies on disks. It should be a good alternative until BD will become supported and affordable, if they ever will???
Good Luck everyone...
PS,
BD players would not play this DVD disks.