Man, I don't know. Why don't you ask Sega? All we've seen so far is a simple teaser page, with an adorable animated silhouette of a clown-shoe wearing girl juggling an apple.
That's all Sega seems willing to divulge about "Project RINGO" on the recently opened teaser page at its Japanese web site. We can tell you that "ringo" means "apple" in Japanese, so we're almost positive this project will involved apples. Or, if Sega's teasing skills are incredibly amateur, Apple.
Given the giant bulbous shoes, which look to be of platform game regulation, we'd think that Sega might have an original platformer up its sleeve. But I guess we'll know more on February 24th (or when the next issue of Famitsu leaks).