There is a lot of music that plays in-game through radios or phonographs that is not on the soundtrack but is instead tracks that have been around for a while now. Sounds to me like a lot of oldies, and good ones.
Can we get a list of them so we can search them out if we would like to? I can't remember if they were in the credits or not.
I love the use of licensed music. I think it better seats the story in reality (especially when it's symbolic). I feel the same way about product placement in movies, but I get a lot of crap for that. lol
EDIT: I heard a song by a female vocalist in the monastery; something about "you'll always find me?" Her voice was really, really soft.
The song from the radio in the Centennial Building in the video archives room is "I Wanted A Lover, I Needed A Friend" by The Coals. Luckily i had already heard of them, but they don't come up on google. Search on Zune or Itunes.
The music over Ending E is Ed Harcourt...The net is calling it "here be monsters", but I think its just a bonus track off that album with no official name. I'm not that familiar with the artist to call it...