I don't think that ABC has killed in anyway, it just takes time for some shows to find their footing. Remember that it took "Cheers" a second season for it to become popular, and with "Seinfield" too.
Networks don't usually show that kind of patience these days. Every so often you'll find an exception like The Office
or Old Christine
where they give a show a chance to build an audience, but then there's usually Emmy nominations tied in with it, and it would look bad to shit-can a show that's been nominated for a bunch of Emmys.
This year, it's probably only because the WGA strike fouled things up so much that some of these shows (Knight Rider, Life on Mars)
haven't already been cancelled; there simply isn't anything else waiting in the wings. The sad part is that Knight Rider
gotten better since its mid-season retool, but now that it's up against American Idol,
it's "game over."