First appearance of Mocha Joe, who would return a decade later as a recurring character in season 10.
Before Larry talks to Mocha Joe about Jason Alexander's dogs, the person buying a coffee is Norman Brenner, who was Michael Richards' stand-in during all nine seasons of Seinfeld.
When Amanda (Cheryl) and George (Jason) are getting cozy on the couch and fighting over the popcorn Jerry says "This is like the greatest relationship I've ever seen you have on the show, I'm watching Richard Benjamin and Paula Prentiss here." This is a reference to the short lived He & She (1967)