The end of Episode III!!!!....
The way I see it, there is a major problem Lucas will have to solve with Episode III: showing anakins fall to the dark side, while at the same time, not giving away that anakin is darth vader, which would spoil the surprise in Empire Strikes Back when Vader tells luke that he is his father. I've thought about it alot, and the only solution i see is that we will NOT see Darth Vader in Episode III, nor will we see the Jedi hunted down and murdered, nor will we see Obiwan spilt up Luke and Leia and go into hiding. Now just bear with me for a second.
If we see Anakin turn into Vader in Episode III, then anyone watching the series in order will know Vader is Lukes father the second we hear Luke's last name. I think in Episode III, Anakin will turn to the dark side, and Obiwan will battle with him. Finally, EPISODE III WILL END WITH OBIWAN (apparently) KILLING ANAKIN, probably in the lava pit.
Now that would be a little dissapointing for those of us (myself included) who want to see the Jedi hunted down, but it works best when you think about the big picture. When we first see Vader in ANH, we will not know he used to be that cute little boy, he will just be one bad-ass sith terrorizing the galaxy. And when Ben tells luke that Darth Vader killed his father, Anakin father, we will know that Ben is lying, but we will think it is because HE KILLED LUKES FATHER, and doesn't want Luke to know. Then, in Empire and Jedi, we finally find out the truth about lukes father, and why Ben said what he did. Anyway, I know thats alot of reading, but I wanted to tell everyone my idea and see what you guys thought.