Stephen Kearse at the New York Times:
The plaques and firsts are the least interesting part of her story, though. Above all, Butler was an observer and ponderer. The probing mind that animates her novels, short stories and essays is obsessed with the viability of the human enterprise. Will we survive our worst habits? Will we change? Do we want to?
These questions led Butler to explore settings banal and fantastical, brutal and tender. Her peculiar, unsettling worlds, rendered in prose trimmed of sentiment and ornament, overflow with desperation and tragedy. She deeply distrusted utopias, saviors, power brokers and escapism. Accordingly, her works are heavy and bleak, full of warnings and catastrophic failures to heed them.
more here.