It looks like Halloween is going to the dogs this year. Twenty-nine million people are expected to dress up their pets next week. That comes out to about half a billion dollars spent on costumes. The number is double what it was in 2010. A list by the National Retail Federation shows pumpkin costumes are the most popular followed by a hot dog outfit. As for total spending including two-legged costumes, that comes out to a record nine-billion dollars.