When Jill's dress doesn't arrive and she has nothing to wear, Tim asks, "Why don't you wear that slinky blue dress that's low-cut...", to which Jill replies that she doesn't have a blue dress. This is a reference to season 2's Overactive Glance (1992) when Debbe Dunning makes her first appearance on the show as Kiki Van Fursterwallenscheinlaw in the aforementioned blue dress. Debbe joined the show as new 'Tool Girl' Heidi Keppert at the beginning of season 3.
When Tim, Jill, & Marie arrive at Jill's benefit you can see a poster for an upcoming presentation of "Billy Riback". Billy Riback is actually one of the producers of Home Improvement, primarily the early seasons. He also has writing credits on a handful of episodes as well.
Final appearance of Joe (Robert Picardo), Tim's annoying neighbor. According to Picardo, he was originally supposed to show up in more episodes, but then got the role of The Doctor on Star Trek: Voyager (1995). While he was at first hesitant to leave Home Improvement out of loyalty and fear of typecasting, Tim Allen, who is a huge Star Trek fan, urged him to take the part when he found out about it.