Show of the week: Royal Wedding

The wedding in London of Prince William and Kate Middleton is predicted by some to be one of the most-watched television events ever. Covering a ceremony at Westminster Abbey that is scheduled to begin at 6 a.m. Eastern Time, Katie Couric will sign on for CBS at 5 a.m., Diane Sawyer and Barbara Walters will host ABC’s coverage beginning at 4 a.m.; and a special edition of NBC’s Today show will stay on the story from 4 to 10 a.m. Noteworthy among cable outlets broadcasting the ceremony is BBC America, whose live coverage will run from 3 to 8:30 a.m. Friday, April 29