With just over 100 days until the July 16 release of JK Rowling's "Harry Potter and the Half-Blood Prince" U.S. publisher Scholastic is preparing a multimillion dollar marketing blitz to stir up excitement. The base theme message "Who Is The Half-Blood Prince?" will appear on airplane video screens, electronic billboards, and online. The New York Times on July 10 will run a crossword puzzle dedicated to the book. Fans will also receive lightning-bolt scars at midnight with their books.