Factual error: When Rose is locked in the room and the bodies come toward her, you can see a modern-day electric light-switch to the side of the door she's trying to get through. When the Doctor hears her screaming for help and runs for her, you can see a central heating radiator. In fact, the undertaker's house has at least two radiators in different hallways. Both are wildly anachronistic for the time period. (00:16:30 - 00:17:08)
Suggested correction: While the light switch is ahead of its time, the heating radiator was invented by Franz San Galli in 1855 and was immediately popular. It's possible that by 1869, when the episode takes place, that Mr. Sneed would have one.
Factual error: The upper peninsula of Michigan is missing on the map of the US shown on Van Statten's monitor.
Suggested correction: In that era of Doctor Who the Earth was being invaded by aliens on a regular basis. Since the story is set in the 'future' year of 2012, anything may have happened to wipe that part of Michigan off the map.
I'm from Michigan and when I noticed the UP missing, I jokingly said to a friend "looks like Canada stole that finally"