Play this game. Don't ask why, just do it.
So basically like I just said, Black has lots of variety in it. Whether you're in a deep woodsy area or in the middle of a town, Black has lots of variety. Each of the weapons is well balanced. Such as that RPG's only have I think 4-5 shots with them, they are very powerful. Then again, the AK-47 has lots of more ammo, but doesn't deal as much damage. Black also has destructible environments in it. Not everything is destructible, but most of it is, which leads to a bad part of the game.
The destructible environments does have a great depth and impact in gameplay, but it could also lower the difficulty. For example, there's this one part where 10 enemies lets say were standing under this big, non-explodable tank of gas. You can obviously just toss a grenade and kill them all tactically, or you shoot the metal things holding the tank up and have the tank fall on them. Another example of this is when these two guys will slide down a rope onto this glass part of a building. You can shoot them two with the super-awsome revolver, or you can easily shoot the glass and have them fall through, which makes it a bit too easy.
All in all, Black is an excellent First Person Shooter. For being Criterions first (I think) FPS, this makes a great start for them, and I hope they continue this series. Then again, knowing EA, I think the series will.