I first saw the news at Forrest J Ackerman, R.I.P. by Mark Evanier. Ok, technically, I first saw it in a link to that post.
I'm assuming, as everyone seems to be doing, that the weekend will bring a lot of informative and/or poignant tributes. As it goes, I may have to bow to the knowledge and experience of those people. My memories of Famous Monsters of Filmland are sadly gray and foggy.
However, to quote RIP Forrest Ackerman by Wil Wheaton, "all of us who enjoy or make a living from sci-fi (or both) owe him a moment of silence and remembrance."