As you may have realized yesterday, I really like Vixen. She was one of the few good things to come out of the Justice League of America's Detroit era, served ably on the Suicide Squad for some time (she and Bronze Tiger kicked much ass together), and was voiced by Gina Torres, the actress who played Zoe on Firefly, in the Justice League Unlimited cartoon.
She is beautiful, elegant, and deadly, and is a black character who doesn't have "being black" a major portion of her character the way that Black Lightning does. She's an awesome, well-rounded character who just happens to be African-American, the same way that Batman is an awesome well-rounded character who just happens to be Caucasian.
Ironically, I also think she's much more approachable, comic-book-wise, than Animal Man, who had similar powers.
Plus there's that whole "Mass of an elephant Bum Rush" that is so freaking cool.