^^
No, Southpark is a completely different style of cartoon. Matt & Trey are genius story tellers. They have a brilliant knack with satire. Their work goes together with much more flow. Many of the characters on Southpark have been so well developed after so many years that making a feature length film would be pretty damn easy... or at least easier than a Family Guy movie.
Don't get me wrong, I'd love it if they tried, I just wouldn't hold out too much hope.
Adios,
Steve