"Les Miserables" is a period musical. Musicals have historically done very well in the Sound Mixing categy, including recent wins for "Dreamgirls" and "Chicago," but musicals are less successful in the Sound Editing race.
"Life of Pi" is an adventure film directed by Ang Lee. Adventure films often do well in sound categories at the Oscars, including last year's winner "Hugo."
"Skyfall" is the latest film in the James Bond franchise. Big-budget action films are often nominated for sound awards, but no Bond film has won since "Goldfinger" won Sound Editing in 1964.
"Argo" is a drama about an attempt to rescue hostages from Iran. Period films with action elements are often recognized in Oscar's sound categories, including "Inglourious Basterds."
"Lincoln" is a biopic by Steven Spielberg, set during the Civil War. War films and Spielberg films have a storied history in Oscar's sound categories, including previous wins for "Letters from Iwo Jima," "Pearl Harbor," "Black Hawk Down," "Saving Private Ryan," "Jurassic Park," and more.