In the episode "Christmas" (6x07) the "That '70s Show" title is decorated with Christmas tree balls again. During the opening credits Christmas bells can be heard. This was used before in episode 4x12.
During the opening credits of the episode where Fez dreams about the cast singing and dancing to some of the 70's most well known songs, the names of the cast members are in silver and two searchlights go across each name. Also, two searchlights go across the license plate at the end of the opening.