This year, the winner of the Best Picture Award will be decided by preferential voting (also known as instant runoff voting, or IRV for electoral nerds). Preferential voting is a system in which voters rank the candidates--in Oscar's case, from 1 to 10--and the votes are considered through an advancing process in which the candidates receiving the fewest number of first place votes are eliminated and the remainder of their ballot votes go to the more popular candidates. This process continues until one candidate has achieved the majority. (This is different from other popular ranking polls, such as the AP college football poll, because the positions are not weighted by points, rather the larger number of top votes that a candidate receives serves to simply keep them in competition during the "instant runoff" process).
The first recorded use of the preferential voting system in a government election was in 1893 for colonial offices in Queensland, Australia. Since then, preferential voting has gained many proponents but not widespread use. Probably the most notable use of preferential voting in the United States is in San Francisco where, in 2004, the elections for city offices began using the system.
Although the decision to go IRV has been met with some harsh criticism from Hollywood insiders, the system really goes hand-in-hand with a larger field of candidates: the last time that the Academy had 10 candidates for Best Picture, in 1943, preferential voting was used ("Casablanca" won). The system protects against an increased number of candidates simply becoming a bunch of spoilers.
The new voting system should give the Academy Awards a much-needed jolt of popular enthusiasm by inviting both accomplished blockbusters ("Dark Knight" comes to mind) and art house films ("4 Months, 3 Weeks and 2 Days") to the Best Picture party. By diversifying the field of contenders and requiring an extensive analysis of the titles by the voters, the new process promotes greater viewer interaction and interest ("what's your top 10...?").
I especially like what a commenter on David Poland's movie blog suggested for the telecast: "They need to treat the nominees as a top 10 list and not 'nominees.' Then, structure the broadcast around the top 10 like American Idol and gradually count down the vote tabs from #10 to #1 throughout the program to create suspense."