Big warning required here. Unless you really want to know, DO NOT click on this link. This spoiler involves the plot of the next 2 films and ties them together with the original trilogy. It is VERY interesting, but in a few ways I wish I hadn't read it. As far as its validity goes, who can say for sure except Lucas himself, but after reading it it's hard to imagine any other possibilities.
You'll have to read through a lot of other stuff first (the BIG spoiler appears about half way down the page) but its worth it.
Anyway, I've warned you so don't flame me for just passing along the info. www.corona.bc.ca/films/details/sw2.html