For people familiar with Bethesda's recent history it won't come as a surprise, but Microsoft announced that the first two DLC for Skyrim will be timed exclusives for the Xbox 360, meaning that PC and PS3 players will have to wait for a month before getting them:
On November 11th, Bethesda Game Studios brings us the next installment in The Elder Scrolls franchise with The Elder Scrolls V: Skyrim. Xbox LIVE will be the first to bring players the experience of Skyrim's add-on content in this revolutionized open-world fantasy epic where players can explore any way they choose.
The first two add-on content drops for The Elder Scrolls V: Skyrim will be releasing exclusively on Xbox 360, 30 days before it's available anywhere else. If you'd like to be the first to break new ground in Skyrim, Xbox LIVE is the only destination that won't keep you waiting.
For more information about The Elder Scrolls V: Skyrim please visit http://www.elderscrolls.com/skyrim/ and http://www.xbox.com/skyrim.
To my knowledge, this is the first time Microsoft and Bethesda have been so upfront about the fact that the exclusive is only a timed one, and while far from ideal, at least PC and Playstation 3 players now know how much they'll have to wait.