Big news folks, today at MGS' 25th anniversary event, the next major title in the MGS series has been revealed to be called
"Metal Gear Solid: Ground Zero".
A short tech demo of the game was also showcased, no footage from said demo has been made available to the public yet, however it was revealed that this MGS title will actually be "open world" and run on the FOX engine for consoles.
Source:
http://www.siliconera.com/2012/08/30...tal-gear-game/
Also here's a bit of promo art they showcased: