When Otis and Shane drive away from Hershel's farm, the Georgia license plate on their blue car reads ES3L251. Moments later, the exact same license plate appears on Dale's white van.
When Andrea confronts Shane about leaving, the shotgun Shane is carrying goes from being held in his hand to having the butt-stock in his shoulder.
When Andrea hands the pistol back to Lori while they're sitting around the fire, she is holding the grip, but when Lori reaches for it, she has it in the palm of her hand, holding it around the cylinder.
If Merle were being treated for Gonorrhea (the clap) he would be taking Doxycycline, not Oxycyclin.
When Glenn, Dale, Andrea, Daryl and Carol are back together discussing the situation, the plot suggests the time of day is nearing dusk, about 7:00 or 7:30 pm, but Daryl's shadow is short, suggesting the sun is still high, enough for the time to be around 3:00 pm.