9.5/10
Great graphics obviously, although that isn't a large selling point for most people. Honestly, this games scales very well and the people who complain that it plays like crap are simply being too over-zealous with their quality options. Turn the quality down and your performance will be fine, even if your machine is a few years old.
Great gameplay:
I like how the land is so huge and you can explore. You don't have to take a certain way to reach an objective. You could drive in with a stolen jeep. You could hijack a boat and attack from the shore. You could swim in with cloak mode on and pick guys off one by one. You can set up explosive or mines and then lure guys out to kill them. You can go into the base through the front door, or climb the huge mountain behind it armed with a sniper rifle and rocket launcher.
Your cover is destructable - so you can't hide behind that cardboard box forever. The enemies are smart enough to blow it to bits. The bad guys also will grenade you and try to flank you at every opportunity. The AI isn't faultless, but at least the soldiers aren't mindless drones.
You are certainly not indestructible. Even though the suit is powerful, it isn't overwhelming, so there is still a challenge to the game and you can still die if you don't make the best use of the suit functions. That adds a different tactical element to the gameplay, which makes the game more than "run and gun".
The environment certainly will be varied. In the full game you will have lush jungle and beaches, but also indoor labs and frozen glaciers.
There are vehicles - jeeps, boats, speedboats, hovercrafts, tanks, a helicopter, a NUKE tank...
Seriously, what isn't to like?