The issues with this week's Rock Band DLC were worse than we first thought. Rush's Moving Pictures album will not be available for purchase on Xbox 360, nor PS3. Apparently some guy called "unforeseen technical difficulties" has screwed everything up. Wait, it gets worse. According to the announcement post on the official Rock Band forums, the problem may keep the album from being available for a couple weeks.
Harmonix is currently shifting the release schedule around to have some tracks out this week, keeping its streak of new content since the game's launch alive and well. We'll be sure to post when we hear something about Harmonix's plans.