Japanese games magazine Famitsu was present at a PlayStation Premier event where the Metal Gear Solid series creator Hideo Kojima announced Metal Gear Online is in the works for PS3.
The quote reads: “Furthermore, the up-to-date work of Metal Gear Online is in the midst of development for PlayStation 3.” Hideo then said the game (or is it just a mode in Metal Gear Solid 4?) will be revealed at the Metal Gear 20th Anniversary Party, which will be held on July 24th, next week.
Further translation from CVG reads it’s the online component that featured in Metal Gear Solid 3: Subsistence. So it’s assumed to have sneak, capture, and rescue multiplayer missions along with Deathmatch and Team Deathmatch.