To be honest, I wasn't expecting much of a change in Modern Warfare 3 from Modern Warfare 2 going into Call of Duty XP. Needless to say, Infinity Ward and Sledgehammer Games blew my mind after all the bombshell changes going into Modern Warfare 3. The biggest change being the new Killstreak system.
Strike Packages, as they are now called, will come in three flavors and are designed for three type of core play styles. Assault is what you remember Killstreaks to be, Support is designed to help aid your team, and Specialist is every Perk you can get. Seriously.
First, here's the list of all the rewards you get for the three Strike Packages:
So as you can see, Assault is pretty traditional. Note the lack of a Nuke option. One thing Infinity Ward gathered from the fan feedback is that stuff like the Nuke is game breaking. So that's where all the balancing comes in. No nuke, no shotty as a secondary weapon anymore, no Commando perk, no Last Stand (except in a Death Streak) and so on.
Then there's support, where you're obviously meant to help your teammates more than anything else. You have more of an incentive to help your team now anyway as you get points for assisting your teammates, getting objectives, and more. You're getting rewarded for helping your team and best of all, your streak doesn't reset after getting killed with the Support Strike Package.
Now here's where you're about to go "holy shit!" (I know I did.) The Specialist Strike Package is EVERY perk (and at Pro status) you can get. So on top of the three perks you go into a match with, you can slowly gain more perks with each kill (sort of like Sharpshooter from Black Ops.) Once you die, the perk streak resets and you have to gain everything again. Imagine how much of a BEAST you can be if you master this! Of course, there is a drawback as you can't call in any air support or the like. Again, balance.
On paper, it sounds like Specialist can be, well, completely unbalanced. I'll be putting this to the test today at Call of Duty XP. But again, Call of Duty's Robert Bowling claims that this is the "most balanced multiplayer experience [Infinity Ward] have ever done." The balance is applied to everything from weapons, classes, map layout, perks and killstreaks.
So what do you think? Change is scary, I know. But I think it's a good change.