I asked the same question on Steve Hoffman forum: "New release is mixed from the original 8 track sessions and the left field media is a copy of the broadcast from a tape source at the radio station before it went out over the air. "
Before I sold my copy, I listened to both. My opinion is the new release is a little cleaner and has a bit more detail. I think had I heard both side by side before buying the new one, I would have been satisfied with my original.