First mention of the friendship/roommate agreement between Sheldon (Jim Parsons) and Leonard (Johnny Galecki).
During the montage, the song "You Can Be My Yoko Ono" by Barenaked Ladies, who also sing the show's theme song, is played. Romona is being compared to Yoko Ono who was John Lennon's wife and is often blamed for the break-up of The Beatles.
According to Sheldon's schedule, Mondays he eats Thai food consisting of Mee krob and chicken satay with extra peanut sauce from Siam Palace; Tuesdays are new comic book night at the Comic Book store; Wednesdays he plays "Halo" and/or watches Battlestar Galactica (2004); Thursdays he has pizza from Giacomo's. Sausage, mushrooms, light olives; Friday is "Vintage game night" (mentioned earlier in The Codpiece Topology (2008)). On weekends he plays paintball.
The comic book which Ramona catches Sheldon reading inside his textbook is Batman #680, cover-dated October 2008.