Based on recent job ads posted by Konami on Gamasutra, it seems the studio is looking to implement multiplayer in one of their games…and it could be Metal Gear Solid: Ground Zeroes.
Among the positions listed by Kojima Productions, of note is for a Network Programmer in Japan, which lists the qualifications needed for the post as some who "Has professional experience and strong ambition for creating large-scale online games for PC/PS3/Xbox360." Another notable job ad is for a Level Designer in LA who wil be "creating and designing solid, visually stunning environments and mission scenarios for single and multiplayer 3D action games."
With Metal Gear Solid 4 having an online multiplayer component, it's not too surprising to think that Ground Zeroes will go the same route. Of course, seeing as Hideo Kojima has gone on record to state that Project Ogre is not Metal Gear Solid: Ground Zeroes, the job ads could also point to Project Ogre instead of the Metal Gear game, no?
However, it does list that it wants developers on 3D action games and large-scale online games — something that both applies to Ground Zeroes as it is a 3D action game and will be open world.
Would you want multiplayer in Ground Zeroes? Come to think of it, seeing as the game will be open world, what kind will it be?