Millennial Media (MM -34.7%) is falling apart in response to its Q4 revenue miss and light guidance. On the earnings call, Millennial blamed the Q4 shortfall on a decision not to participate in certain low-end, performance-based, ad campaigns (often tied to app downloads), and the failure of some brand ad deals to materialize. No explanation is given for the guidance beyond seasonality. The comments are bound to raise concerns about competition. Ad prices rose 10.3% Q/Q, and Millennial has confirmed its purchase of ad targeting platform Metaresolver. P -3.8%. VELT -2.4%.