

Clark Gable, Claudette Colbert in Frank Capra's 1934 comedy It Happened One Night (top); Ray Milland, Jane Wyman in Billy Wilder's 1945 drama The Lost Weekend (bottom). The first and last best picture Oscar winners by way of the preferential voting system.
The winner of the 2010 best picture Oscar will be determined through the preferential voting system, which in the last six or so decades has been used to determine the Academy Award nominees in most categories.
According to the Academy of Motion Picture Arts and Sciences' press release, the preferential voting system will be used because it "is [the] one that best allows the collective judgment of all voting members to be most accurately represented." (In theory, perhaps. In practice it may be a different matter altogether. See more information on the preferential voting system.)
The chief reason for this change has been the Academy’s Board of Governors' recent decision to extend the Best Picture category from five to 10 nominees. The preferential voting system was used to select the best picture Oscar winners from 1934 to 1945. There were 12 best picture nominees in 1934 and 1935; 10 from 1936 to 1943; and 5 in 1944 and 1945. From that time on, Academy members could pick only one film as the year's best; the winner would be the film that received the highest number of votes.
The 2010 Academy Award nominations will be announced on Tuesday, February 2, 2010, at 5:30 a.m. PT in the Academy’s Samuel Goldwyn Theater in Beverly Hills.
The 2010 Academy Awards ceremony will take place on Sunday, March 7, 2010, at the Kodak Theatre at Hollywood & Highland Center. In the US, it'll be televised live by ABC.
This whole preferential thing sounds way complicated. How can we – or they – be sure that the ballots were counted correctly since you have so many ways things could be miscounted because of the "preferential" messy system?