Sweeney...
The differences between animal and Animal are quite hard to describe within a two hour and forty-five minute show without confucifying the audience. There's so much going on, that that is the least of all problems. Hell, if they went there, why not discuss Ozma, and how she has been locked away somewhere.
When comparing both books, you have to realise that they are both very different from one another. They changed the plotline to make it simple so that the "Oh My God! Wicked is SOOO Awesome!" fans can understand them without them having to "think" about the show. Keep in mind that there are a lot of hidden undertones within the show that one would have to pick up by seeing the show more than once.
I, personally, enjoy Wicked. I think the simplifications make it an easier musical to watch than if they had stayed with the original idea. My mother hated the actual book, and I had to beg her to see the show. She loved it.
It's entertaining.
Imagine if Les Miserables had stayed true to the book, explaining every single detail - then it would have been a three week musical instead of a three hour one.
That one even changed the book around a bit.
"Do you know what pledge time is, Andrew"? said the PBS Executive.
"Yes", Lloyd Webber replied. "My 50th birthday special must be one program that gets done a lot."
"No", mused the man from PBS heedlessy. "Not so much. Our Stephen Sondheim Carnegie Hall concert. That's a big one."
Spoons, forks and knives seemed suddenly to suspend their motion in horror, all around the table.