It's called Makeruna Wassoi! and it's being released in CD form for purchase during the H!P Summer Concerts this weekend.
It's only 800yen so I hopefully can score one on Yahoo! Japan Auctions from a random wota. I have a thing for collecting these special CD releases (Chisato's Romantic Ukare Mode, Aichan's Yume Kara Samete, C-ute's Rakuten Eagles cheer song, etc) so this would fit right in with my collection.
Thanks to Hello!SayuNii for the info.
PS, here is a concert rip of the song if you haven't heard it yet: