I asked earlier if anyone had any pointers on moving an iTunes 11 library to iTunes 10.  I didn’t want to downgrade iTunes 11 to iTunes 10 on a single computer, but rather wanted to move an iTunes 11 library that exists on one Mac to an unused iTunes 10 library on another Mac.

The answer appears to be an almost-perfectly-unqualified yes.  Via Twitter and app.net, I got several suggestions.  I decided to try the one that was the easiest: export my iTunes 11 library to XML, and then import it into iTunes 10.  I figured if it didn’t work, then I probably hadn’t lost too much time.  It worked!

So here are the steps that I followed:

1. On my old Mac, I launched iTunes 11 and went to File -> Library -> Export Library, and saved my library to a flash drive.
2. After that had completed on my old Mac, I quit out of iTunes and ejected the flash drive that held the library file, and also ejected the external hard drive that housed the actual media in my iTunes library.
3. On my new Mac, I connected both the flash drive and the external hard drive.
4. On my new Mac, I launched iTunes 10 and went to File -> Library -> Import Playlist and selected my exported iTunes library.  It began churning away.  Since that library has ~35k items in it, it was clearly going to take awhile, and I left it to do its thing while I ran some errands.
5. On my new Mac, I checked and everything that I was most concerned about (playlists, ratings, etc) was there!  All of my metadata had been preserved, and my media files had been moved to my new Mac’s hard drive.  (Thankfully, I had enough space.  They’ll be moved off to an external hard drive soon.)  I spot-checked several songs, playlists, videos, and podcasts, and everything was there.
6. To confirm that I had everything, I compared the size of my new iTunes media folder with my old iTunes media folder, and discovered that the former was larger by about 8 GB.  I discovered two things that didn’t get copied over: all of my Books, and all of the application files for my iPhone and iPad.  The former is surprising, since it had gotten everything else, the latter is unsurprising.  So on my new Mac, I went to File -> Add to Library and added those books and applications back in.

Next up is to move my photo library from my old Mac to my new Mac, which should be a lot easier, and then sync my iPhone and my iPad to the new Mac and make sure that everything works.  Once that is done, I’ve got a few clean-up items to do on my old Mac, and then I can let it go to its final resting home.

Many thanks to Brian Webster for the original suggestion.  I’m pleasantly surprised that it was so easy.