I'm torn on the whole hood up/down thing. I think it would look pretty bad ass with it over his head, and the hood would hide his face during the jump hopefully covering up the possibly fake looking digital face. But at the same time, Obi-Wan fighting with hood over his eyes, face darkened out? Sounds a little too Sith-ish.
But, I'm sure Lucas knows that we all know that he doesn't go to the dark side, so he might not be as worried about that imagery.... I kinda hope he goes with the hood. It'd look cool.
I also really like how he mentioned the trailer and the "good enough" shots. I always wondered why in the Mystery and Forbidden Love trailers there were so many shots that were different in the final film. I could understand George changing his mind, but that was a lot of mind changing. Now I understand that he probably just told them "these are the shots I want in the trailer, give them a once over so they look basically like they will in the film, we'll fix em later." I recall the speeder chase scenes in the trailer looking rather fake and everyone getting worried - but the film looked fine. Glad to know this. It'll make me (and hopefully everyone else too) not worry about any apparent effects problems in the first trailer this time around.