That is very saddening news. Though I've only seen one of the original television productions of the Quartermass stories, I've seen the films, and read the screenplays for them... and they deserve their place in the history of science fantasy, definitely. I've had very limited acquaintance with anything else Kneale has done, but nonetheless he was quite talented, and I'd very much like to see more of his work back in print over here.
As for The Stone Tape, there is a review of it here on the Chronicles for those interested:
http://www.chronicles-network.com/fo...tone-tape.html
Some of his short stories were also included in various anthologies, including a couple edited by Ray Bradbury. There is a fairly good bibliography of his work here:
Nigel Kneale