In the six major categories there was at least one upset almost every year. Since Slumdog/Boyle and Ledger seem to be sure things, I would expect an "upset" at "Suporting Actress".
Cruz isn't heavily favored anyways and "Vicky, Cristina, Barcelona" isn't your typical academy-type movie and she probably has the toughest competition compared to the categories.
Besides taht, Departures was a longshot at +1300 at "Best Foreign Film" and came way down. Wouldn't bee surprised if they beat out "Waltz with Bashir" tonight.