Translates as "Rhythm Heaven".
GBA / 3800 yen / 3 August.
This game was previewed in Famitsu a couple of weeks ago, but apparently word never got out that it's made by the Made in Wario team, as noone seems to be talking about it.
It's full of mini-games based on rhythm. The games generally last 2-3 minutes each and while the characters from Made in Wario are gone, there seems to be some new cute stuff in place of them. Difficulty increases through precision required, rather than increase in tempo, and it gets pretty bloody strict by the sounds of it.
Here's the Famitsu clip neo2046 scanned a couple of weeks ago: