Modern Warfare 2 already had some extremely strong killstreaks in the game, and Sledgehammer has not only brought every single one of them back in Modern Warfare 3 but also thrown a few extra ones into the mix too. Every killstreak has its own benefits, with some being very quick and easy to use, while others are a lot bigger and capable of covering more ground, but it's become clear since the game's release that there's a select few that players are prioritizing over the others because of their overall effectiveness on the field.