CBS Television City, home to ABC's Dancing With the Stars, was evacuated last night after someone at the Dancing production offices received a threatening letter containing white powder. ABC said, "The substance was determined to be talcum powder. It will be transported to a regional lab for further testing. A joint investigation is continuing." Why would someone send such a thing? Deadline hints: "The authorities have not confirmed online reports that the letter was addressed to Sarah Palin's daughter, Bristol Palin, who surprisingly made it to the final round of the dancing competition despite a string of so-so performances." Some people get really indignant about that type of thing. [Deadline, Daily Mail UK]