In one of the farm flashbacks, Beth is holding Judith. The camera angle frequently changes. Each time the shot is front-on, Judith is awake and looking around. Each time the shot is from the side, Judith is sleeping on Beth's shoulder.
During the prison flashback scenes, Carl's voice is notably deeper than it was in the first half of season four. This is obviously due to Chandler Riggs' becoming a teenager.
When Carl hears the man screaming and calling for help he runs to him, and as Rick follows he can be seen carrying the Uzi he took from the Claimer he killed earlier. However in the next shot when they start running from the walker herd Carl is carrying the Uzi.
During the 'round up', Rick is firing his .45 automatic. The slide locks back as they are running and Rick is firing towards the roof line. In the next shot, as they turn the corner, Rick fires off another round, then reloads, but the weapon should have been empty.
When Rick draws his pistol and takes Alex hostage the sound of a hammer being cocked can clearly be heard, however the hammer on Rick's .45 is still in the upright position.
At 4:24 Rick is shown picking a dead cottontail but it's clearly a stuffed toy cottontail.
The little recon, way of entering, lack of leaving backup on the outside, etc. are as if Rick and the others have completely forgotten their experiences with Woodbury and The Governor.