This could be interesting; I've alwasy thought that LeBron ought to be better at posting up his opponents than he is. He's big, strong and athletic and really is a good rebounder. In time, I could see him being a dominant PF, although it would be a hybrid PF/SF role that he would play. His offense is already devastating, but with a much better post game it would be... devastating-er (!)
It will be interesting to see how this plays out. Putting him at PF leaves him open to more abuse and cheap shots away from the refs.