Steam now offers the Windows edition of the Escalation DLC for Call of Duty: Black Ops, Treyarch's first-person shooter sequel. Here's word on the $14.99 USD pack: "'Escalation', the second Call of Duty: Black Ops map pack, contains 5 all-new exceptionally varied maps; featuring 4 Multiplayer maps and an epic Black Ops Zombies experience with all-new playable characters." On a related note, the promised free multiplayer weekend for Call of Duty: Black Ops is now underway on Steam. Here's the deal on that: "If you already have Steam installed you can click here to install or play. If you don't have Steam, you can download it here."