This book is EPIC! :D It was probably 5x better than Little Brother.
I really like Doctorow's writing style and how he explains complicated theories and how the character thinks. It's really eye-opening to the sort of things that go on in the world, that we can't just ignore anymore.
I even think the cliff-hanger ending was done well. Even though you don't really know what happens afterwards... If it was a happily-ever-after ending, it would seem wimpy and predictable, but if it was a sad ending, that would just add the depressing-ness onto the 43 dead main characters :(
All in all, I rate this book 10/5 stars.