From TMCnet:
"Competitive nights The 9 p.m. Thursday time slot will continue to be the most competitive, with networks pitting their top shows against one another.
This year it's "Grey's Anatomy" on ABC, "CSI" on CBS, "The Office" and "Community" on NBC, "Supernatural" on CW and "Fringe" on Fox.
Fox moved "Fringe" to this time slot, which could be the kiss of death for the science fiction/fantasy show.
It will be hard to lure a similar audience away from "Supernatural," which also uses the odd and the weird as a draw."
Source: TMCnet.