This script will change the file type of the selected AAC tracks to "M4B " and file extension to ".m4b", thus making them bookmarkable. (That is, the track will natively resume playing wherever you left off the last time you played it.) Additionally, when used with iTunes 7 or later, deletes and re-adds each track so it will appear in the Audiobooks Library. Ratings, play count, last played date, skip count, and skipped date are preserved.
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