Anticipating new books
At Edge of the American West, there is a fun thread about anticipating new books by your favorite authors. There was no criterion really specified for how to choose the authors you list; here is what I used: an author all or most of whose back catalog I have read*, and if I read about a new book of whose being published, I would run out to the bookstore and buy a copy.
Most books I've bought in my life have been used; buying just-published books is a pretty new experience. I think this is a complete list of the books that I've bought on the day of their publication: Mason & Dixon, The Keep, Against the Day, Other Colors.
(And come to think of it, I've pre-ordered a couple of books from Amazon or similar, so received them at the time of their publication. So probably should add to the list Monk's Music, and Autobiographies of Orhan Pamuk which I await anxiously, and the two volumes so far of Moomin comics.)
*Except Saramago, I've only read two of his books.