The only thing that is really starting to bother me is when an "American" shows up at the hotel. Not only are the accents completely improbable (anywhere from haltingly unsteady to a mix between New York and a country twang) but they are using expressions that are really not used in the United States. One guy actually said, "quite right too," which is so completely British, that when the Doctor said it in Doomsday, most of us Americans misinterpreted it as "quite right to."
I really think they should get a real American to proofread these little bits.