I don't see how he hasn't had mainstream success for a while. Beavis and Butthead did very well for him and King of the Hill was a staple of Fox's Sunday lineup for the longest time.I've always loved Mike Judge's work and it's good to see him getting more 'mainstream' success as others are starting to catch on to how funny he is, which is cool and about time.
South Park is significantly better but I do enjoy his work.I still argue King of the Hill is the best animated show ever made. At the very least it had by far the best characters. It stayed strong throughout it's entire lifespan instead of Simpsons of Family Guy who are just completely unwatchable in later seasons.