So, I bought the game Tuesday, booted it up that night, and couldn't make it to the first save point because I was so tired. I tried it again tonight, and played the first couple of missions.
It's an interesting game. It's part mini-Metal Gear missions, part army management game. You can capture guys that you incapacitate and add them to your team. Your team levels up, and unlocks new weapons and allows you to upgrade weapons you already have.
The story is a sequel to Metal Gear Solid 3, and a prequel to the NES Metal Gear games.
Good stuff if you're a Metal Gear fan.