I thought that it was SO obvious that Palpatine / Sideous were the same guy, that it couldn't be true. I thought there was going to be some thing to do with the force that 'they would become one' or something like that. And that would tie in with why the Jedi, especially Obi-Wan, dissapear when they die. But, Lucas just chose the obvious. I have to admit that I knew it all along, but I was still dissappointed.