Is there going to be another Buffy the vampire slayer movie?
As far as I know yes but it's in development and if my sources are right it will be out in 2012 at the earliest
Is there going to be another series of Outnumbered?
Is there going to be another Eureka series?
Eureka is currently at season 4.
Is there going to be another season of Knight Rider?
According to the IMDb page- the show has been cancelled after Season 1 which has been put on DVD.