AA at About.com posted a transript of a chat with Lucas. Here's a clip:

Lucas admitted the writing process can burn him out too, which is why he brought on Jonathan Hales to co-write Episode II's script. "I've used co-writers a lot. The first one I wrote myself, but the other two were co-written. Phantom I wrote myself, but when I finished it I was tired and burned out and I took a vacation for about a month. As a result of that I did four or five drafts [of Episode II]. It was to the point where I could show the script to the crew and they could start working on things, but it was one week before we started shooting. I knew I wanted to do more work on it, but I was about to direct the movie. So I brought in Jonathan, whom I'd worked with before on Young Indy and who I trusted. We sat down and I said, 'This needs to be fixed, this needs to be fixed.' I turned into a director and I let him be the writer."

With regard to the use of special effects, Lucas said the biggest challenge on Episode II was the digital creation of Yoda. "If I couldn't replicate Yoda digitally I was in serious trouble. I couldn't have made this movie. We tried to make him digitally on the first movie and we couldn't do it, but if we hadn't accomplished it here I would have had a pretty silly end of the movie."

Finally, does the competition from Spider-Man make Lucas nervous? "In that tradition it's a very good film. Sam Raimi is a very good director. It's funny, because people talk like Star Wars in part of the comic book genre, but it's different. A lot of people on the outside, they look at this stuff and they see comic book film and science fiction, and it's all the same to them, and it's not. Each is very individualistic and has its own genre demands."