When Peter and Chris are recording the first episode of "Handiquacks", Joe is the one who says that their hands are slippery because of the new wooden stove that they just bought. But in the episode that Peter shows to Fox, Quagmire is the one who says this line.
In the scene in the bar where Peter shows his drivers license to brag that the took the new photo drunk the expiration date on his license is 11-11-2011. Cleveland then says "....I just got my new license a month ago" but the expiration date on his license is also 11-11-2011.
When Peter, Meg, and Chris are brainstorming the first episode of their show, the couch is 45 degrees to the walls, yet when meg is left alone on the couch it's now parallel/perpendicular with the walls.