Color provides a huge amount of "key information".Note orientation: All the C's are marked with green, all the notes of the major scale are colored and the black and white keys (the flats and sharps respectively), are marked with colored dots. The coloring makes use of the color wheel with a dash of my interpretation of notes as colors (I think of C as Doh = root/mild = Green, So = dominant/intense=Red, etc)
perhaps gaudy at first, but I've found this color scheme helps guitarists "get" the chord
structure in 2 minutes or less,
instead of the normal 5-10 minutes I used to need. I find it works very well in assisting reading music.
My other expectation is that it meshs well with the way the brain hears music; each note in the scale has a special feel when the ear knows it's place and color.
if you see a score with 3 flats, you play 3 black keys (Bb, Eb and Ab),
and pretend they are "blackened" (a.k.a. flattened). If you see 2
sharps, you shift over to play 2 white keys. Transposition, which seems
so hard on a piano, becomes utterly obvious on a colored jammer.
as with key transposition, if you see a sharped note, move over to the
"white"; three notes right, one down. Flats are the converse. It takes
about a week for this to become automatic.
Musical education, helping arrange and create new songs, and provide insight, to name a few effects.
It looks interesting, cool and fun - a piano is so bland. I suspect that the white keys of the piano is a contributor to the loss of perfect pitch most children experience. I have heard of at least one person who attributes her retention of perfect pitch to having a colored toy piano.