Just to put a different slant on the discussion:
I recently watched a PBS show where Paul Simon was being honored for doing whatever it is he did over the years, and most of the numbers were his songs being covered by some of the most surprising artists: Lyle Lovett, Stevie Wonder, Alison Krause, Damian Marley... Of course it was in a "tribute" sort of format, so that was expected, but each of the artists did the songs in their own way. It was fun and educational to see what they could do with all those "signature" Simon songs.
-Glenn