I don't know has he finalized the design, but probably some sort of elongated DVD cases so manuals fit IIUC.
It'll be a single piece of Injection-Molded Polypropylene, with Two Living Hinges.
The outer plastic jacket (for artwork) will be made of clear Polypropylene, or clear polyethylene.
Inside, on the Right, will be a press-to-release hub for Game CDs (and/or a place to put Saturn or SegaCD Action Replays and Memory Cards).
Inside, on the Left, will be some tabs to hold Game Manuals in place.
Don't worry; they won't scuff up any manuals with Foil, or crush any raised wording.
Like Arseen said, the design isn't finalized, but they will closely resemble an Extra-Tall DVD Case.
ETA on the Sega CD/Saturn Cases is early 2014.