Epic have officially announced that the first piece of DLC for Gears of War 3 has been delayed. The Horde Command Pack was scheduled for release today, however Epic have stated due to "a technical issue late last week during some of our final testing, we were unable to resolve the problem today to ensure a timely release." They're working as fast as they can to get the pack out, however no date has been given. It's unknown whether we'll see the content in a matter of hours, days or weeks.
Update - The Horde Command Pack is now available for download!