This We Three Kings of Orient Are is in the major of F with the b flat while the other book version has the same song but it's in the keys of G major with the F#; they just transcribed the same song in different majors. This book also have the Offenback Barcarolle slightly different and simpler compared to the other book.
Of course, I love that they included a short Jingle Bells, and Good King Wenceslas. I liked the Russian Round, it has many dynamics and staccatos.