UPDATED: Make Bookmarkable v2.5
The popular Make Bookmarkable has been updated to v2.5 and is now compatible with iTunes 7.7.1. Make Bookmarkable will change the file type of the selected AAC tracks to "M4B " and file extension to ".m4b", thus making them bookmarkable. Additionally, when used with iTunes 7 or better, 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.