To be honest I didn't know that this was considered a Young Adult book before I read it, although it soon became clear. The fact that it's told from a teenager's point of view and is intended for teenagers explains a few of the book's weaknesses such as the slightly fantastical, wish-fulfulment elements, the "don't trust the oldies" theme, the one-dimensional villains and the slightly Hollywood ending.
On the other hand it's an inventive, page-turning thriller, full of fascinating and clearly explained (for non-hackers like me) information on technology, privacy and security (read the afterword too, which tells you how much of this stuff is real, as opposed to science fiction) and a little on the history of civil rights in the US. The politics aren't subtle, but considering that it was written in response to Bush-era anti-terrorist legislation that's understandable.