A noir dame is, in short, the kind of female anti-heroine discovered in 20th century detective novels. She could also be seen in 1940s and 1950s pulp films like "Double Indemnity" - good when she's bad, bad when she's good, etc. In the 1920s, this stereotype was usually called a "vamp," and the French "Nouvelle Vague" film critics of the 1960s raved about the "femme fatale".
But in this case it refers to a female "night owl", writer and business owner, formerly seen sniffing around the streets Chandler walked in La Jolla. She writes about science fiction, fantasy, noir, mystery, history, and whatever else twitches her fancy, and will hopefully help out at Wikipedia as it continues to grow.
Partners in crime - real and imagined - include a tortoiseshell cat named Ivanova, and a fluffy grey and white kitty, known as "His Girl Friday," or simply "Friday" when she wants "Just the Facts".
As an actual writer and editor (though no Teresa Nielsen Hayden), she's happy to pitch in. Please feel free to contact her through the Noirdame:discussion page if you need help with an article, and she'll see what she can do.