Once upon a time, not so long ago, songs imported from CDs to iTunes on my iMac stayed in the CD format. They had to be converted to AAC format manually.

Over the last few weeks, I've imported a few tunes, and they've all appeared in AAC format right away. Cool.
"Seek for the merit in others, even the tiniest shred. Then do the same in yourself"
-Reb Nachman