Well, this is sad news -- I just found out coming to this page.
I can't believe this wasn't more prominently covered, since she was such an icon of dance (note the way Janet Jackson used her in the "Alright" music video).
For those who want to remember or even to discover Cyd, my favorite of her movies are:
Singin' In Rain
The Band Wagon
Brigadoon
It's Always Fair Weather
Movies get no better. And for those who doubt Cyd's acting chops, don't forget that dancing is acting too. No actress expressed falling in love better than Cyd did with that first leg extension in Central Park in
The Band Wagon. And "Dancing In The Dark" commenced. . .