WG Map Pass available?

So as you might have heard, it is going to be possible to purchase a War Games Map Pass on release day. It will be similar to that found in the legendary edition and includes two exclusive helmets and one emblem (not saying this is not in the LE.)

I have two questions:

1) Where/when can I buy or preorder this map pass?
2) Does it include early access to the six specializations?

Thanks.

you buy off of xbox live marketplace. nope doesnt come with early specializations. But it does come with an exclusive armour and emblem. it costs 2000 MS points (here in canada you can actually buy 2000 MS point cards for $25 from EB games)