After the Golden Globes, the Screen Actors Guild, the Producers Guild, the Director Guilds and the British Academy awards; there is little to no question that Ben Affleck's Argo is the overwhelming favorite to win Best Picture going into Oscar night despite the fact that the Academy did not nominate Affleck for the Best Director award.
You may or may not know this, but unless you're from the 1930s, it is very unlikely for a film to only win Best Picture at the Oscars. A lot of the winners sweep the awards winning anywhere from five to eleven statues. Now, given the circumstances of this year, it is also unlikely for Argo to sweep the awards. There really aren't that many categories where it could win, but it will take a statue wherever it can get one. And Film Editing is one of those places.
Film Editing is such a hard art to judge (good editing isn't supposed to be noticed by the spectator), that most of the time the category skews very hard towards the Best Picture front-runners. This year, for example, all five movies cited are Best Picture nominees (Argo, Lincoln, Life of Pi, Zero Dark Thirty, Silver Linings Playbook). Whether you consider Silver Linings Playbook to be one of the best edited movies of the year is debatable, but the nomination is also proof that having Best Picture momentum will help you score a nod in this category.
I don't know if Academy voters are aware of this, but by awarding Argo, they'll be giving the statue to William Goldenberg, who is nominated twice this year. His other nomination is for his collaboration with Dylan Tichenor in Zero Dark Thirty. And while I think the relation between rhythm and substance makes the work in Zero Dark Thirty superior, there's no denying that Goldenberg cut (or helped cut) two of this year's best films.
Will Win: Argo
Should Win: Zero Dark Thirty