There’s no slowing down Harry Potter. The boy wizard’s sixth installment, Harry Potter and the Half-Blood Prince, grossed an additional $26.8 million on Friday, bringing its three-day total to an impressive $107 million. HP6 is opening stronger than its predecessors but is still tracking behind Transformers: Revenge of the Fallen, which had earned $127.8 million by the time it reached its first Saturday. HP6 will be buoyed by its family-friendly PG rating, though, and is expected to post some impressive numbers this weekend. Stay tuned for updates.