go here
http://www.alphapuprecords.com/ and get teh podcast
listen to it and watch how the title in itunes changes and so does the album artwork even tho its all one track.
im not 'exactly sure' but, because its mp4 or acc or something along thoes lines the file type is able to hold more information and so the producer(real producers here not some random person on the internet putting out a podcast) is able to add that kind of stuff. also when you burn the podcast it seperates each bookmark into its own track. pretty nice.
i know garageband now has a new itunes mode to help make podcast. but what programs you can use right now to edit things like this i do not know. im pretty sure the more expensive audio editing software would be able to do this.