I guess cars become "chick cars" when 50% (plus or minus) of a model, are seen driven by them. Name brands are very important to women so Porsche Boxter, Mazda Miata, all BMW and Mercedes convertibles, seem to be on their list. Nissan 370Z is not yet on that list, although it may become one.
I wish I could find the "Two and a half men " episode where a character buys a Porsche (Boxter), and the rest of the episode some body tells him my wife, girlfriend or daughter drives one too.
Episode title: That Old Hose Bag Is My Mother.
Tu.tv - Videos de Entretenimiento - Video: two and a half men 2x22 Subtitulado Sorry this was the best I could find.
The last three Caymens I've seen were driven by mature women.