The link above is for purchasing, here's the link with the details of the offer: http://www.greenmangaming.com/the-bureau-xcom-declassified-o…
It's 10% off atm ($45), and you can choose either $8 cashback or $12 credit. If all the bonuses unlock, you'll be getting The Bureau: XCOM Declassified + 1 DLC, Spec Ops: The Line, XCOM: Enemy Unknown + 2 DLC, and the classic XCOM games, for $34.
XCOM Declassified seems to be a kind of sequel to XCOM: Enemy Unknown, but set in 1962. It still has team based combat, but it's an over the shoulder shooter rather than top down turn based strategy. Its release date is 20 August 2013.
Here are some hands-on previews:
Giant Bomb (video): http://www.giantbomb.com/videos/quick-look-ex-the-bureau-xco…
Rock Paper Shotgun (article): http://www.rockpapershotgun.com/2013/07/22/hands-on-the-bure….
The bonuses depend on number of pre-orders. To begin with, you get the Codebreakers DLC for free (not sure what this is), and it has now reached level 2 so you get Spec Ops: The Line for free, and once it reaches level 3 you get XCOM Ultimate Bundle (the previous game + DLC) and all the classic XCOM games. Unfortunately they don't seem to list how many pre-orders are required, or what the progress is towards them. Personally I'd be surprised if they don't all get unlocked, but obviously it can't be guaranteed. These are the bonuses:
Level 1 (unlocked):
Get 10% off when you pre-purchase The Bureau: XCOM Declassified and get the Codebreakers DLC free!
Level 2 (unlocked):
Your FREE copy of Spec Ops: The Line is unlocked when the number of pre-purchases hit Level 2
Level 3 (locked):
When pre-purchase sales hit Level 3, as well as the previous benefits, you will also get a Free XCOM Ultimate Bundle, featuring XCOM:Enemy Unknown, Elite Soldier DLC, Slingshot DLC and 4x XCOM Classics (Steamworks) titles including UFO Defence, Terror from the Deep, Apocalypse and Enforce.
If you don't have a GMG account yet, feel free to use my referral code (means we each get $2 credit after you purchase): http://www.greenmangaming.com/?gmgr=kucipixo
Looks great. Holding my horses until it gets unlocked to level 3