MTV has yet another article online called Harry Potter And The Half-Blood Prince’: What Plotlines Need To Be Included To Make Us Happy. They mention SPEW, Narcissa Malfoy, Kreacher, Quidditch, and Occlumency. They say “But since the early films were being made while the “Harry Potter” series was still incomplete, some plot oversights will need to be rectified in order for major events to occur in the final three films. Here are a few that need to find their ways back.”  Here is what I agree most with:

Occlumency: In “OotP,” Professor Snape teaches Harry occlumency so Harry can keep Voldemort out of his mind. Though the lessons don’t go as planned, Harry does delve into Snape’s mind once to see his worst memory: Snape as a schoolboy at Hogwarts being harassed by Harry’s father James and calling Harry’s mother Lily a “mudblood,” one of the worst insults in the wizarding world. Harry misinterprets the importance of the scene — as did the filmmakers behind “OotP,” who only left in small fragments of the flashback and left out Lily altogether. The true importance comes as one of the biggest moments of the series at the end of “Deathly Hallows” — and makes Snape arguably the most interested characters in the “Harry Potter” universe.