At a press conference on May 13, 2008, Hideo Kojima announced a marketing campaign and agreements with several companies to promote the game. Apple computers and monitors feature in the game and an Apple iPod is an in-game item that Snake can use to change the background music, listen to in-game
podcasts and collect hidden songs scattered throughout the game. ReGain Energy Drinks are used in the game as a Psyche gauge booster, and Sony Ericsson mobile phones are used, specifically by Naomi and Vamp.Konami and Ubisoft put an unlockable costume in the game for Snake, Altaïr from the Ubisoft stealth game Assassin's Creed.
Initially revealed on April Fool's Day 2008, Kojima later announced that it would actually be in the game, unlockable by doing "something special". To obtain the attire, the player must acquire the "Assassin Emblem", a nod to the game's title (or input a password in the Extras section).Konami had originally planned to organize grand launch events in Tokyo, but some of them were canceled with the "safety of participants in mind" in light of the Akihabara massacre on June 8, 2008.
Also, in Act 4, when Snake enters Shadow Moses, Snake receives a call from Otacon, instructing to insert a second disc into the console (itself a reference to the original Metal Gear Solid), but then says that there is no need as the disc inserted is a dual layered Blu-ray Disc, and that the game is on the PlayStation 3.
