Supernatural what is going on with season 6 next new episode?

Does anyone know when Supernatural will return with a new episode pfr season 6? There was suppose to be a new episode on Friday on the 28th but it didn't happen and now it looks like according to my dvr that it won't happen this week eitherbut Smallville is back with its next 10th season episode. I have my dvr set up to record only first run episodes of my favorire shows on the cw. So why is Smallville back with new episode this coming Friday the Febuary 4th but Supernatural is not? Does anyone know why this is?