For those that bought the Limited Edition you have this already! It's coming soon! For the PC version of the game it will be ready on December 13th!! I hope we get it on at least one of our Conquest Servers as the maps are very popular in Battlefield 2. In my old clan during the hay day of Battlefield 2 we had 1 server with nothing but Karkand and Wake Island 24/7 and we did very well with it always being full ( I would no suggest doing the 24/7 thing for awhile as it does get boring after 6 or 7 rounds) but it will be exciting to see the maps on the Frostbite Engine!!
Link about the release:
http://blogs.battlefield.ea.com/battlefield_bad_company/archive/2011/12/02/battlefield-3-back-to-karkand-out-on-pc-and-xbox-360-december-13th.aspx##
More on Karkan found here posted by Capt. Karow:
http://www.politeandfriendly.com/modules.php?name=Forums&file=viewtopic&t=10730
This solider can't wait!