Borderlands Mad Moxxi's Underdome Riot DLC Now Available

Gearbox Software has released Borderlands' second set of DLC, Mad Moxxi's Underdome Riot, on the Xbox Live Marketplace. 800 points gets you:
Mad Moxxi's Underdome Riot is an add-on pack for Borderlands that includes a new cooperative arena game mode and a stash to store your gear. Are you god's gift to gun fights? Think you're the best? Wanna prove it? Then help us celebrate the grand opening of Marcus Bank (a subsidiary of Marcus Corp) by killing hundreds and hundreds of people in Mad Moxxi's Underdome Riot, the only competitive arena around where your next of kin can be assured that you're coming back famous . . . or not at all. (All proceeds are kept by us).
There's still no word on when PC and PS3 gamers can expect the add-on, but hopefully we won't have to wait too long.