When Grace spots Joan Collin's character of Helena Barnes in the restaurant Karen turns around and says "Oh, LORD LOVE A DUCK!" This is a joke reference to one of Joan's early film appearances in the mid 1960s in the black comedy "Lord Love a Duck"; in which she had a cameo role alongside Roddy McDowall and Tuesday Weld in 1966.
Grace says to Helena Barnes (Joan Collins), "I'm like one of those losers when they meet William Shatner at a Trekkie convention" after meeting her. Joan Collins made a guest appearance in the Star Trek (1966) episode "City on the Edge of Forever", starring William Shatner.