Pratchett displayed his usual good humour when making the announcement, confirming that he is wrapping up his current novel, Nation, and already planning the next, Unseen Academicals.
"I would just like to draw attention to everyone reading the above that this should be interpreted as 'I am not dead'. I will, of course, be dead at some future point, as will everybody else. For me, this maybe further off than you think - it's too soon to tell. I know it's a very human thing to say "Is there anything I can do", but in this case I would only entertain offers from very high-end experts in brain chemistry."
Pratchett has sold 55 million copies of his work, which now comprises 36 Discworld novels, four Discworld map books, three 'Science of Discworld' books, seven other Discworld tie-in books and 11 non-Discworld novels, the most famous of which is probably Good Omens (co-written with Neil Gaiman). He is the second-biggest-selling living fantasy writer (after JK Rowling) and is the most shoplifted author in Britain, which he takes as a compliment.
Best wishes to Mr. Pratchett and his family and here's to many more books, Discworld and otherwise, to come!