I think it would be cool if we posted what we wish or think the wow movie plot will be. This is NOT meant to be news, but purely speculative.
I would like to see a movie about Thrall. His story has always been interesting to me. His story incorporates many already done storylines, ie gladiator/slavery/spritual journey/ coming to grips with abusive caretaker etc etc, but I still think it would make a great story. I don't think that is the way it will go however.
It would also be cool to see a movie about Medivh. He is a HUGE lore character, but we only get a little glimpse of him in CoT. If you didn't play the 1st Warcraft game or read any novels he is still pretty obsucure.