The second-to-last downloadable content collection for Call of Duty: Modern Warfare 3 has hit Xbox Live, accessible to those that do not have a Call of Duty Elite membership. While PC and PlayStation 3 will have to wait about a month to get their hands on this content, all platforms are getting a double XP weekend to mark the event. The double XP will last between today and Monday, and Infinity Ward promises a double weapon XP event later this month.

Infinity Ward's Twitter account detailed the XP weekends, and also gave word that some short-lived problems with the Vortex download have been resolved now.

As previously reported, Chaos Pack includes four Spec Ops missions (Special Delivery, Light 'Em Up, Vertigo, and Arctic Recon), along with three Face Off maps (Vortex, U-Turn, and Intersection), and a new wave-based survival mode for Spec Ops called "Chaos." The next pack, set to hit in September, will include five new multiplayer maps. As per usual, the PC and PlayStation 3 will get each of these packs a little later.