Deliberate mistake: Nearly every night scene inside the house is lit by very bright lights shining in the windows from outside. Yet every time anyone is outside the house, it's still just as dark. There is no light source from which these lights could possibly originate.
Revealing mistake: IChat is used to make a second call to Professor Jonas, only this time we can see Professor Jonas is online under "Bonjour". Without too much detail this would mean that Professor Jonas is in the same house (on the same LAN) as Ellison. (01:31:55)
Continuity mistake: His best selling novel changes in quantity on the shelf in his office. After he signs a copy for the officer they increase in number, and lean one way then the other.
Continuity mistake: At the beginning of the movie, when the family is unpacking their belongings in the new house, we see the young daughter painting a figure in red on a wall whilst talking to her father. Eventually she fully colours in the figures red dress. A couple of shots later, however, there is an empty patch now on the figures dress. (00:04:43)