The flashbacks featuring a young Peter and Lois take place a long time ago, probably 20 years or so. Yet in the flashbacks, Carter looks exactly the same as he does in the present.
When Glenn Quagmire introduces himself as an Ensign (a Naval officer), he is wearing an enlisted man's uniform.
When Peter rips off Death's hand, Death stabs him in the eyes with his fingers. However Peter is wearing glasses at the time.
After Carter gives Peter the check in the hot tub, in one frame he is seen without eyebrows.
Right before Peter crushes the talking spider, the eyes of two people behind him jump off their faces for a frame.
At the dog track, Stewie says Louis is "screwing up my 6-2 Quinella", however, in betting, a Quinella is always listed by the lower number first as it doesn't matter which 2 of your bets win or place, so it should be a 2-6 Quinella.