US cable network AMC have decided not to pursue the six pilot scripts they've had in active development since March: alien first contact drama The Voyage from writer John Shiban (X Files, Breaking Bad), The Man With The Golden Ears (based on a Danish series about a music exec balancing work and family), The 4th Estate (about the investigation of a congressional scandal), The Wreck (set in the world of Southern college football), American Made, and an untitled racing project.
Instead, AMC are very likely to renew their acclaimed crime drama The Killing and continue with existing shows Mad Men (returning spring 2012), The Walking Dead (likely returning this October), and Breaking Bad (due in June.) They also have their brand new Western drama Hell On Wheels already filming for a premiere this autumn.
Those six unmade pilots aren't dead. They will continue to be developed, so there's a chance some of them will get picked up in 2012.