just quickly
I just wanted to add quickly, as it was mentioned earlier in this thread, a little something regarding the midi-chlorian thing.
Apparently, and i say this because I remember George himself mentioning it - it was either on the dvd, or in the "mythology of star wars" film - The force has always been to do with midi-chlorians (although I'm sure during the OT, the name midi-chlorian wasn't even close to being created yet) George just never got round to putting it in the Ot (yes, his reasoning was THAT lame)!!
So, I guess it's always been part of George's thinking, but never visualised on film for the fans/filmgoers.
I also remember him saying somewhere, that he made the force more spiritual in the OT, as it gave his galaxiy a kind of mysticsm, like, the presence of a higher being - something that every religion can relate to (not just christianity).
He obviously took ep1 as a chance to explain further what the force is - personally I don't feel that it needed to be explained any further. The force as an unexplained presence works just fine for me!