At some point Apple snuck in the feature I've spent years waiting for: ability to generate 256 Kbps AAC on the fly from Apple Lossless when synching portable devices. (That feature has existed at 128 Kbps for a while, but I wanted the higher bit rate).
This means I no longer need to keep two copies of much of my music -- making the iOS iTunes Apple Remote vastly more usable, saving disk space and all kinds of iTunes admin headaches.
This will cost me a bunch of time to delete the AAC stuff (I have very few AAC only things in my library, but still I don't wish to lose them by deleting all AACs wholesale -- and the "Find Duplicates" feature doesn't always work, as sometimes the AAC predates my Apple Lossless version and CDDB info for the same CDs changed over the years.)
Thank you Apple -- and I'm curious if anyone knows how long ago this feature came into being.