There seems to be a lot of misunderstanding here over whether certain T-shirts or signs are banned. From what I understand, there is nothing special for this game. The Cavs just reminded fans that they do not allow shirts or signs that are vulgar or innappropriate. It is the same thing with every team in the NBA, but the Cavs knew that there were going to be a lot more than normal with Lebron returning, so they just wanted to get the word out, so fans are not taken by surprised when they are told they cannot display something vulgar.