As we’ve known for a while, Metal Gear Online will be included with MGS4. It will be a basic online service and will be upgraded over time. I know I’m going to like MGO. 
MGS4 has been in development for 4 years, and they say some stuff won’t be discovered for a long time, months, maybe even years later.
Here are some other details:
The opening credits (of MGS4) were designed by Logan, the people that did the hugely successful ipod ads.
The story visits more locations and embraces more styles than any MGS to date.
A ‘virtual range’ will be included from the main menu. Here you can test the huge amount of weapons in MGS4 as well as the various advanced CQC techniques in the game.
The game will feature various details to play around with such as highly detailed and fashionable consumer gadgets.
There will be one hell of a big bang of a final to the game. Not a whimper. This will blow you away.
Snake is a slave to injections that keep him alive.
The sneaking play of the originals with it’s air ducts and cameras has now become a fast pace living battlefield of traps and innovations.
The control system is ‘revised and improved’
The Gekkou (the mechs with organic legs that make mooing sounds) will work in packs to hunt you down. They can sense past your optic camo if they think something is amiss.
Snake will have two new energy bars that makes Snakes advanced age impossible to ignore:
Stress: This rises in response to fight conditions. This can work with him, giving him hightened senses such as accuracy and sustained damage being halved. But if in this condition for too long, snake will crash causing him to become exposed to his illness. a drag on a cig will help him calm down however.
Psyche: This affects your general state of mind in the field.The balancing of these two bars will affect your progress.
You can use a camera to sneak away from your mission objectives and record incidents happening on the battlefield in secret. Some can be ‘unpredictable and dangerous’ There is something special about the camera this time around but EDGE were not allowed to say what.
There is a “surprising degree of explorative freedom” in the game. You can choose to engage in battles if you wish, or just ignore them. Friends and enemies can be gain this way if you do choose to help one side out.
Drebin (the arms dealer with the small monkey) will be important to the story and will also act as Snakes weapons dealer.
Productions values transcend modern video games: A Hollywood grade surround sound and moving track score by Harry Gregson Williams. Electrifying cut scenes and a sense of closure “more suited to Return of the King than Halo 3″.
MGS4 details from EDGE: This will blow you away
