I would like to start by clarifying that the Physical Warfare Pack is a time-based exclusive. If you do not pre-order Battlefield 3 at a retailer carrying the Physical Warfare Pack, don?t worry. We will unlock the contents of the Physical Warfare Pack for free to all Battlefield 3 players later this year.
The Physical Warfare Pack will be available as a pre-order bonus all over the globe. Right now, the UK is the only country where it has been announced, but stay tuned to get constant updates on where you can pick this up in your country. And remember, if you do not pre-order, you will still get access to this content at a later date, free of charge. If you do pre-order, you will get access to it from day one.
http://blogs.battlefield.ea.com/battlefield_bad_company/archive/2011/06/16/physical-warfare-pack-available-to-all-battlefield-3-players.aspx##Back to Karkand is a massive, themed expansion pack available a period of time after the base game, developed by a separate team here at DICE -- the same team that brought you Battlefield: Bad Company 2 Vietnam. If you played Battlefield: Bad Company 2 Vietnam, you have a pretty good idea about the scope and ambition of our expansion packs. This is so much more than just four remixed maps.
If you pre-order Battlefield 3, you will be able to play Back to Karkand at no extra charge as soon as it is released, but it is not day one DLC and it is not on the base game disc. We think it?s a sweet deal, and it?s available to everyone everywhere. If you do not pre-order Battlefield 3, you can still buy Back to Karkand separately and play it as soon as it is released, the very same date as anyone who pre-ordered. In other words, there is no segmentation of the community when we launch the base game.
That should clear up any confusion. I personally didn't care all that much, but many apparently do.
What does the forum say?