A full database with everything Metal Gear has go online for the US Store, its 'safe' for newcomers to MGS4 as it will "blacked out" spoilers until the game is completed.
It comes with an extras section which already gives gamers some new camouflage and in-game music for free, no EU Store mention yet.
"The MGS4 Database is a free, downloadable interactive application that contains the official knowledge base of everything that is Metal Gear, reaching all the way back to the very beginning of the franchise. Including complete storylines, character profiles, relationship diagrams, and much more! The MGS4 database is a great way to catch up for someone new to Metal Gear, as well as a useful resource for any veteran of the series, with complete official details on every aspect of the intricate Metal gear lore," read Brandon Laurino's post on the official .
If you're planning on uncovering the past of Metal Gear then you might want to set aside some time - a lots happened and a lot more needs explaining. Bring coffee, lots of it.