Fox made a mistake by scheduling "Head Cases" on Wednesdays at 9 (ET/PT), when it, a drama, went against five other dramas on broadcast networks!
Fox should have considered making a change to put a sitcom into that time slot for the Autumn months. At least it would have been good counterprogramming.
On the other hand, I believe the "American Idol" results show will fill the 9 to 10 P.M. hour beginning in early 2006.
One other thought: Don't get used to Fox's "Killer Instinct" (premiering tonight, September 23rd, at 9 P.M. ET/PT). Given that (1) Friday-night television viewing has declined significantly in recent years as more and more Americans are going out that night (usually to the movies), and (2) Fox has not had a hit on Friday nights since "Millenium" in the late 1990's, I expect that "Killer Instinct", which will be pre-empted anyway for a couple of weeks due to baseball playoffs, will not come back after the baseball playoffs end.
Expect "Killer Instinct"'s run to last all of two episodes.