It's about time for an update, I think. I mentioned earlier that I was having no luck with an H.264 Paramount title, and unfortunately I'm still stuck. However, the other reason for the delay was a VC-1 issue. Even though the short clips that I was testing with worked fine, I ran into problems when trying to convert a whole movie, where QuickTime would cut off the video at the 2 GB mark. However, this has now been resolved!
All of the Windows tools mentioned work in VMware and do not require Boot Camp. All of these steps are for VC-1 HD DVDs. Ensure that you have plenty of hard drive space available; I recommend 50-60 GB in Windows and 25-30 GB in OS X for an HD-30 disc, more if you don't want to delete your intermediate files once you've finished with them (Edit: Shared Folders are a better idea so that you don't run into arbitrary space restrictions).
I recommend starting off with a short video before spending too much time on a full movie. All of the Universal discs that I've tried have a 32-second file called unilogo.evo that can be used for practice
1. In Windows, use
AnyDVD or similar to copy the movie to your hard drive. Please note that this tool is not free, although there is a trial available.
2. Use
EVOdemux to split the feature.evo file into MPA and MPV files. Although they'll have long, complex names by default, I'm going to refer to them as movie.mpa and movie.mpv. You can delete the EVO files once they are demuxed.
3. Use
vc1conv to convert the MPV to a .vc1 file ("vc1conv movie.mpv movie.vc1"). You can then delete the MPV file.
4. Use
vc12avi to encapsulate the VC-1 content into a set of AVIs. You can now delete the VC1 file.
5. Use
eac3to with the -libav switch to change your MPA from E-AC3 to regular AC3 ("eac3to movie.mpa movie.ac3 -libav"). You can then delete the MPA file.
6. Merge the set of AVIs into one big one with
VirtualDubMod. You can then delete the partial AVIs.
7. Transfer the AC3 and large AVI onto the Mac side, and shut down VMware. Everything's done in OS X from here.
8. Ensure that you have
A52Codec and
Flip4Mac installed so that QuickTime can read the sound and video.
9. Open the AC3 file in QuickTime Player and export it to AIFF. Check that the resulting AIFF plays correctly, then you can delete the AC3.
10. Open the AVI file in
MPEG Streamclip and re-save it as MOV. You can then delete the AVI.
11. Open the MOV in QuickTime Player, Select All, and Copy.
12. Open the AIFF in QuickTime Player then choose Edit > Add to Movie. This will paste the video into the file.
13. Save out to a new MOV and you'll have a complete, playable file! You can delete all other intermediate files at this point.
14. At this point I had heavy corruption in the video. I'm not sure what the cause is (possibly my system being too slow to decode the video in real time, due to the VC-1 codec being less efficient than on Windows). However, exporting the video to another format (eg. H.264) worked perfectly. Note that the free version of Flip4Mac will watermark any exported video. You need
Player Pro (which is the cheapest of the various "editions") to perform the final export.
15. Enjoy your exported file!
Notes for the above steps:
2. Double-layer movies have two files, feature_1.evo and feature_2.evo. When you select the first in EVOdemux, it'll automatically find the second and merge the output into a single file. Theoretically you could also have feature_3.evo on a 51 GB disc but it doesn't look like we'll ever see one of those. It's also worth mentioning that while feature.evo does seem to be the most common filename, it's not set in stone. If feature.evo is missing then just look for another huge file

3. I'm not exactly sure what this step does. Apparently the video needs to be played at 23.976 fps but vc12avi will assume 29.97 unless you run it through this tool first. The end result is that if you skip this step then you'll end up with the video playing too fast. However it may not be required for all discs.
5. You need to eventually convert to WAV or AIFF, and although eac3to can do this I had problems with it. A future release of eac3to may be able to do the conversion directly.
9. The third-party encoder that I use can't read AC3, hence the conversion to AIFF. You may be able to get away with staying in AC3 depending on your requirements.
10. QuickTime has difficulty with VC-1 in AVI. One of my movies would cut out at the 2 GB mark and another would not play at all (displayed a white screen). Changing to MOV fixed this issue.
I will update this post later with links to the tools required (edit: done), and will also clarify any steps that you get stuck on. Feel free to ask questions below and I'll do my best to answer them