According to reports, McDonald's is pushing franchises to remain open on Christmas this year. It did the same for Thanksgiving, noting the potential for sales. The company is not commenting, but says that its up to franchises whether they want to open or not. If workers do work on Christmas, they are unlikely to get overtime pay for working on a holiday. Most employees are part-time, and need the extra hours.
See "McDonald's Christmas Memo Suggest More Workers May Clock In On Holiday", Dave Jamieson, The Huffington Post, December 19, 2012