Red Alert 3: Uprising, the expansion for Red Alert 3, was released via digital download today. You can head to EA's site to learn more about the purchase options. There is a launch trailer here.
In addition, there are a number of contests giving away free copies of Uprising. Community Manager Aaron Kaufman is running one himself on his Twitter account. More details on his here. RADEN also has one running, with a rather neat trivia question.