Obviously Wonder Woman is the top female character of the DCU and that likely won't change anytime soon, but I always considered Catwoman as the number 2 female. Catwoman has held her own successful title on many occasions, she's appeared in all of the Batman cartoons and shows and has been portrayed by multiple iconic actresses. When the DC/MK crossover video game was made she was the only other female chosen apart from Diana. It was pretty difficult not to see her as the second most important/popular/iconic female in the DCU.
Fast forward a few years and now Harley Quinn is the one with the solo title, spin-off books and appearing pretty much everywhere. Harley is the character that just appeared in live-action in the DCEU (before Catwoman mind you) portrayed by one of Hollywood's youngest brightest stars. She's the character almost everyone is obsessed with! Heck she got announced for Injustice 2 before Selina, leading some to even speculate Catwoman will sit this game out. Harley and Wonder Woman are almost always depicted together in fan art whereas a few years ago it was Diana/Selina.
Have things changed? Has Harley Quinn surpassed Catwoman in popularity and icon status? Is it safe to assume Harley is now the number two female while Selina is number three or four (Supergirl is pretty popular these days)? Thoughts?