The fact that the colored dancers were willing to march against the discrimination they were facing, KNOWING it would get them arrested. Also, the fact that Tracy was willing to give up her spot as a dancer just to support what she felt was right.
Edna getting onstage and performing. The fact that she was insecure at first and afraid of leaving her house because of her weight and she was willing to dance on national TV with millions of viewers watching - now that was AWESOME.
The black dancers finally mixing with the whites at the end.
And in the 2007 film, Amber moves on, showing interest in one of the black dancers (the two can be seen teaching each other dance moves in the background, at one point) and telling Velma "I lost, Mom! Let's just deal with it!" after Tracy wins.
Tracy and Link's kiss at the end of the 2007 film.
Hell, that Tracy, Maybelle, and her dancers staged such an elaborate coup in the first place (with some help from Corny Collins, no less).
In the 2007 film, Edna gets her revenge on Velma when Velma admits to Amber that she rigged the votes. Edna, Wilbur, and the camera man turn the camera on her and she tells Velma that she is on national TV, causing her to get fired.