Awesome news! I wasn't that interested in the anime, but I can dig a single release.
Mita Mao, Hata Sawako, Sato Amina
Ishida Haruka, Watanabe Mayu, Iwata Karen
Sato Sumire, Yagami Kumi, Nakaya Sayaka
Great line-up
They all have interesting voices (obviously) so it should be interesting to see what their song(s) will sound like.