Is there any such info on a supposed 4th Sonic game for the Dreamcast?

I'm reading Unofficial DCM (issue covers the consoles 2nd E3 showing I believe) and it mentions "Three new" sonic games either mentioned or on display at the event. That was the E3 where SegaNet was starting to kick into high gear with Sega showing their stradegy for the service (Free Rebate for a DC system if you sign up) and upcoming line up of games to utilize SegaNet (QIII: Arena, NFL/NBA 2K1, Tetris, Magic:TG, PSO, Black and White, etc). One of the games they mention in the mag being developed for the service was "Sonic Square".

Can anyone care to elaborate on this?