Steel Diver: Sub Wars has been rated "G", with a cautionary message stating that the online experience could change during play. There's no mention of the format, but we're assuming for now that it will be on the 3DS, just like the original game — although this time it will naturally be download-only.
It shouldn't be a direct port, however — Shigeru Miyamoto has already stated the free-to-play business model will drastically alter the way in which the game plays.
Steel Diver isn't the most obvious choice for this kind of title, but it could prove to be a valuable experiment for the company. Will you be supporting the release, or do you think free-to-play is an area Nintendo should avoid? Let us know with a comment.