Dunno, there are so many, aren't there? It seems that the newer episodes all seem to include one-time characters that even have a very minor role, even if they are the center of attention. I don't know; what happened to the days when the character roles were short, and the show focused on the silly sponge and his cohorts instead of the ever-growing list of pointless contemporaries?
However, I will continue to watch the show, no matter how painful it may be.