I've been slowly converting my CD collection to MP3s (why, I don't quite know; it's not as if I have an iPod). The most annoying factor is the need to be there to change to another disc when it's done encoding everything. However, another hint about the fact that the system will offer to play CD images made me try making and encoding from an image... and it worked.
So, if you want to batch up several CDs, and have several gigs to blow on this quest, you can make disk images of a bunch of CDs, mount them all at once, and drop them into a playlist to be encoded ... then go off to work while your computer crunches sounds. I presently have Audion working on seven CDs, and will let it go all night. I'm not sure if this trick would work with iTunes, as I don't use it.
Now, if only I could convince Disc Copy to make the CD images instead of having to use Toast.
Mac OS X Hints
http://hints.macworld.com/article.php?story=20020611094502977