Apart from the beaming problems reported in
http://code.google.com/p/lilypond/issues/detail?id=1619 I find 2 other
strange changes compared with 2.13.58 (not 59). Les Nereides has lost a
hairpin in the 4th bar. I don't believe the regtest has been changed, so
this seems critical. In song-repetition.ly, the lyric word "si" is moved
slightly to the right. I don't understand why this would happen.