Everything below is my opinion only:
I thought that this week's show was an evenly funny offering, not an "instant classic" (tm) but a worthy addition to the Seinfeld pantheon nonetheless.
I most enjoyed Kramer's storyline since I love it when he goes out of his way to accomodate society's rejected. The billboard ending was great and Jackie's closing line ("This is the worst of my many public humiliations" -- paraphrased) was perfect.
The sex:smarts theory storyline was out there but it was fun watching George's character change. Similarly, Elaine's metamorphosis was good for a few laughs. It was typical George to have him seriously consider giving up sex for the benefit of mankind.
Jerry and the school subplot was decent as well and was highlighted by Jerry walking in line for the fire alarm evacuation.
And I can't forget Jerry's justification for eating Kramer over George and that he'd *try* George if some others were having him. :)