UPDATE: Variety changed their figure to $22.2 million! That makes it an even bigger haul, and an even easier claim for the record.

Finally the box office is working on the side of good! After two weeks of headlines about Transformers 2 and its annihilation of the competition, Harry Potter and the Half-Blood Prince is the new superstar, having debuted with midnight screenings last night that brought in an estimated $20 million. If that figure holds, it beats the $18 million record set by The Dark Knight last summer to become the highest-grossing midnight opening of all time.

By way of comparison, Variety cites the midnight screening gross of Order of the Phoenix, which was a paltry $12 million in comparison. Unless the estimate is dead wrong, Half-Blood Prince will easily leapfrog past that and likely the previous movie's $139.7 million five-day gross.

I guess the question now is, can Potter top Transformers 2's five-day gross of $200 million? It has a PG rating on its side, which means every family you know will be crowding into theaters. But it doesn't have the inflated IMAX tickets, given that Transformers is still stomping around on all the country's giant screens. I'm betting Half-Blood Prince won't quite reach $200 million, but it will still be fun watching a movie that's actually good blow up the box office-- the first time that's happened since this time a year ago, when The Dark Knight set all the records to beat.