The last thing I noticed when I listened to the first disc of Live at the BBC a few days ago is that "long" in the line "Tears keep a-fallin' all night long" in "Crying, Waiting, Hoping" is sung with a melisma (A C#, I think), which musically gives a sense of duration.
I referenced Buddy Holly's original, but it doesn't contain this feature. Evidently, it's something the Beatles added.
