It's some sort of edition that costs slightly more than the standard one. It most likely contains some pre-bonus DLC (multiplayer most likely) or some pre-order pack, like the Escalation or Annihilation packs from Black Ops.
An Achievement
They do nothing besides earn achievements.
therer are 2 or 3
still TBA
There are actually some youtube vids on that. I watched one of em and it was a big help. [=
it is coming out in a couple months. The pack is called Rusengence pack and it includes 5 maps. 2 from call of duty modern warfare 4 and 3 new ones :)
possibly, but its not likely, with the release of modern warfare 3.
Modern warfare 3 is better
The intervention is not in modern warfare 3. Modern warfare 2 has the intervention.
Modern Warfare 3 is not in 3D.
Modern Warfare Mobilized(the DS port of Modern Warfare 1) & Modern Warfare 3.
I believe it is in mid-June for X-box, not entirely sure though. There is a Call of Duty: Modern Warfare 2 - Resurgence Pack released June 3 2010 for the PS3 and Xbox 360 for the second Map Pack. see related link