I've only read two of her books--The Female Man, years ago, and We Who Are About To... more recently--but the impact they had on me was enormous. I've been meaning to read more for the longest time, and now I will. I think I'll start with a re-read of The Female Man, though--much as I loved it, and much as it changed me for the better, I don't think I was prepared then to receive all it had to give.
She was everything science fiction should be and very rarely is: experimental both in style and content, feminist, vicious, sure as hell not techno-utopian*. She recognized that "lowbrow" writing is as important as any other kind--she wrote essays on Kirk/Spock slash fiction** and if I'm not mistaken actually gave "slash" its name--but refused, as so many who share in that recognition end up doing, to infantilize that writing or to be infantilized by it herself.
*Though I may have a post in me at some point about how even the classic sci-fi writers with the worst techno-utopian reputations weren't quite so simple.
**Here the often-problematic Teresa Nielsen Hayden unproblematically and charmingly remembers Russ's interest in these things, mentioning her observation that, in some contexts, "Spock is a woman." I've long wanted to write an essay about that very thing (in contexts other than slash, which I have no knowledge of or interest in beyond the most glancing "huh" reaction), but hesitated because a) I'm not a woman myself, and b) I don't write cultural criticism essays often, though I frequently want to.
She didn't write much the last few decades of her life, due, I'm given to understand, to crippling pain resulting from a back injury. Awful. I had heard some vague rumblings in recent years that she was starting to write again, and I had always had it in the back of my head that some new late-period Joanna Russ was coming, was to be looked forward to. As with any highly brilliant, highly experimental artist, I was excited to see what later works would be like--you never know how people as singular as her will change with time. Now, who knows if there will ever be anything else from her--I tend to doubt it. Still, she has so much already on offer that I have no experience of--I've barely touched her fiction, and her essays not at all.
Still, for someone I have so little genuine knowledge of, I had quite a shock when the "Joanna Russ, 1937-2011" headlines started showing up in my reader after her death Friday. She was important, and she was wonderful.