I have read both of them. I had the 2005 version, but loaned it to my aunt. When I decided I was going back in 2006, I bought the new version. For the most part the two versions are very close. The only changes I noticed were some of the reader feedback was different, the reader feedback was in blue ink, and that some of the ratings had changed. The only tour plan difference was for post-Everest opening. They deal with that in the Animal Kingdom touring plans.
Overall, I enjoyed rereading the new version, but didn't find much new information.
ttfn,
TT