The latest hire in online tech outlets smacks of cannibalism. Silicon Alley Insider, the vanity blog vehicle of former Wall Street stock analyst Henry Blodget, has lost managing editor Peter Kafka to AllThingsD, the vanity blog vehicle of Kara Swisher and Walt Mossberg. Dow Jones makes for a steadier parent than AlleyCorp, the tech-startup holding company of DoubleClick cofounder Kevin Ryan. But one would think Swisher, who confirms the hire and says Kafka will start at the end of October, might have first raided the vast hordes of reporters working in the faltering medium of print before feeding on her own kind. Let's just hope she lets Kafka get out more.