The New York Times has a slideshow of the release of Harry Potter and the Half Blood Prince around the world, and when you view it, it becomes apparent that different countries have quite different book covers for the book.
The Australian cover is the one we found online the other day at a rumor site that had a leaked copy of that same image. It actually has some plot points in it.
We were surprised at our release gathering at Barnes and Noble — there were tons of people there, and lots pf people, both children and adults, who were dressed up. I snapped some photos of people who had cool shirts or fun costumes on; eventually I’ll put a photo page together.