South Park ending? No way, it's still Comedy Centrals highest rated show, even after 10 seasons. They would throw whatever money Matt and Trey asked for to keep it going. Granted it's not as funny as the old episodes (Like the Towlie ep, probably my favorite 30minutes of t.v. of all time) but it's amazing that I can still laugh at a show after 10 years, that just shows that Matt and Trey are very creative guys.
As for Trey's involvement in Saul, a lot of people don't seem to realize how interconnected the comedy circuit is. If a comedian thinks someone else is funny they'll tend to try to help that person out. It's all about doing something funny, not the money or the networks you work for. Comedy Central is adult swim's biggest competitor and still Trey did this, what does that say?
Cast off this taint, and become taintless