I just finished reading Extras, the final book in the Uglies series by Scott Westerfeld. The first three books in the series play more like a trilogy and Extras kind of felt like...well, an extra. It does have some of the characters from the first three books, but the main focus is on a new character, Aya. It is also set in Asia as opposed to the North American setting of the first three books.
Extras checks back with humanity three years after the completion of Specials. The world has undergone another massive change and the results are mostly good. I really enjoyed this series. It makes one wonder what the world will really be like in five centuries and what effect our current actions are having on that future. I think no one, or at least very few people, will argue with the notion that we are not taking very good care of our planet. As the population grows and technology advances, it appears as though we are speeding that destruction. The Uglies series explores what that might mean when compounded over a few hundred years. Scary, but very interesting.
Now if you will excuse me, I am going to go take out my recycling and hug a tree.