Amazon.com
announced today that more than 560,000 copies of
Harry Potter and the Half-Blood Prince have been pre-ordered through their website to date. They have also added an "Hour-by-Hour Harry Potter Meter" on their
site, showing the exact number of pre-orders of the book (right now it's at 567,985). 789,000 copies of
Order of the Phoenix were pre-ordered through Amazon.com in 2003.
Update: According to
The Guardian, Bloomsbury's stock rose 7.5 points today (to 377.7 points) due to Amazon's announcement. And now, less than ten hours after we posted this story, more than 10,000 additional copies of the book have been pre-ordered