Mind you i think that is all of the original Vocaloids?
Miku, Ren/Len, Kaito, Meiko and i think even (forgot he rname..) pink haired gal too??
Mind you though.. Gumi is not... so maybe he will pop up on there?
Or maybe not because there is already a purple haired guy in Project Sekai as it is.. (well.. Purple with a hint of blue..) which is Shunichi Toki's character..