Advertisers, beware—must-see-TV Thursday has evidently been replaced by Sunday. According to AdAge, for at least three TV seasons, Sunday has been more expensive to advertise on than Thursdays. This fall, it cost $2.23 million to buy prime-time ads on all the broadcast networks on Sunday, compared to $2.03 million to do the same on Thursday. Currently, Sunday Night Football is the most expensive television show to advertise because it's essentially DVR proof. That doesn't mean Sunday's the only way to go, though. One advertising expert said that it's really dependent on what you're selling. Thursday is the only night of the week for retailers and movie studios, while Sunday is the best night to push new goods and services.