When Joey and Phoebe are in Joey's kitchen eating baby food and discussing their plan to set up Ross and Rachel on horrible dates, in the background, the door to Rachel's room is sometimes open and sometimes closed.
Rachel's necklace disappears and reappears during her conversation with Ross.
According to the exterior shot, Ross is waiting for his blind date in Delmonico's restaurant. However the interior looks nothing at all like the real Delmonico's interior, which is one of the US's oldest restaurants and a New York institution. They do, however, have a crab cake appetiser.
Joey has his regular fully-grown eyebrows in this episode, despite his statement that Rachel has been staying with him for just 5 days since he got his eyebrows waxed (in the previous episode: 'The One Where Monica Sings'). This is impossible: eyebrows take months to fully grow back after shaping.
Phoebe purposefully sets Rachel up on a miserable date with Steve (Jon Lovitz), who was introduced in the first season episode, "The One With The Stoned Guy" where Rachel waitresses for Monica's "audition dinner" for his restaurant. Rachel appears oblivious to the fact that when they had met before, he was stoned and the audition went horrible and makes no mention of their prior acquaintance. She goes forward with the date anyway, most likely to appear polite even though she may implicitly recall their first encounter.
In 'The One with the Stoned Guy', Steve the "stoned guy" restaurant owner (Phoebe's massage client) visits Monica's flat, where she tries to serve him a meal and Rachel is Monica's waitress. A few years later, in 'The One with the Blind Dates', Phoebe sets Rachel up on a date with Steve, however Rachel seems to have no recollection of the eventful evening when she first met him, and says "Phoebe tells me you own a restaurant."