Lucas originally planned for 3 trilogies, then decided to drop 7-9. 7-9 Were supposed to be about Han and Leia's children.

I used to have a link to a site where almost the entire movie was displayed in screenshots from the movie, even had some gifs of lightsabre battles, but it's down now. Judging from that site episode 3 will pwn 1 and 2.