Reading this thread, as a HD1 user, here are a few thoughts:
The "wrapper" for the MP3 files is most likely transparent to the user. As SS now remembers the location of MP3 files, I think you will be able to Drag and drop MP3 files to a SS 2.3 album. From there, you can most likely transfer to the HD3 and when doing select MP3 rather than an ATRAC conversion rate as you do now. I think the wrapper will go on when the file transfers. Since the overhead to add the wrapper would be tiny, it would add imperceptable time to the transfer. I think the MP3 file would not be duplicated, but kept as is in it's existing location, unless you convert it to ATRAC. This is speculation of course, but would fit the existing logic of SS.
The addition of USB charging is very nice for the HD3 and shoud be a serious consideration to buyers thinking about HD3 vs. HD1/2 choices. This part is not going to be upgradeable. It might also explain what appears to be a slight weight increase for the HD3, which is being quoted as 130g vs. 110g for the HD1. The deletion of the cradle is too bad. It is handy for charging. But perhaps with USB charging, just plug it in at night, your done.
Using groups rather than playlists is not great. On the other hand, you can sort the groups on the HD1-3 manually in SS and they will appear in that order in the Group mode in the player. This is nice to make your most favorite groups appear at the top or bottom of the list. Also, the shuffle function is more flexible than the ipod, but you have to understand the "play unit" idea they have to use it properly. Once you do, it provides great flexibility.
Overall, the navigation on the Ipod is so much faster that it wins hands down in that aspect.
SS is not as good as itunes, slower, less elegant, but some opinions of SS are impacted by whether the user has had bad luck with it. In Aeriyn's case, where it crashes all the time, of course you'll hate it. There is no excuse for the software to be that buggy. I had this problem with the pre 2.x releases, but it has proven perfectly stable for me in the post 2.x stage, so I can live with it. It does some nice things also. You can tag a file with a document or text so sometimes I tag songs in SS with the guitar chords and tab to help when I play along. Nice to have it all in one place. Overall, I find SS workable and I have a 20+ GB database.
The MSRP in Tokyo will most likely be discounted 10-15 percent, if not on day one, perhaps within a week or so. BIC is showing it on their website with a 10% point credit right now for release on Dec. 10. Sometimes the credit in the shop is more and can change for special offers on weekends sometimes.