I will say right now, expect Michael Clarke to open. He's opened many times, arguably played his best cricket there and has recently been used more there. His style suits the Powerplays more than the death.
I don't think Hopes is a contender, Clarke's average is double for the position and if he does get a run it will be short lived. Australia wants power from the top order and although an earnest fighter, Hopes is not a heavyweight. The squad named even suggests that Hopes might actually move down to no. 8.
Haddin might also come in, as a straight-swap to preserve structure, but I think the difference is that Clarke appears to be pursuing the opener's position, while Haddin has so far suggested only that it is within his repertoire, not that it is his preference.