There's not much I can say, except this makes me too damn sad... A direct blow to the heart.
Eric was a damned good man, who did more for science fiction and fantasy... and fellow SFF writers... than any other author of the last 30 years... Probably since Ben Bova.
Eric was a huge force in the sea change that publishing has undergone in that time, all the while keeping up a pace of publishing new work, while fighting aggressive cancer... he was irrepressible, and he is irreplaceable.
From Baen Books:
It is with a heavy heart we share the news that Eric Flint has died.
We will have an official statement to come, but for now, we mourn the loss of one of the finest writers in the genre, a generous colleague and mentor, and a dear friend.