Very interesting, well written book. It presents a scenario and follows things to logical conclusions, sets rules and keeps them. Interesting character development, too.
The not so great? Well, it suffers a bit from the "this person is involved in *everything* that happens" syndrome, but that's par for the course in scifi, and I have learned to live with it.
And this is totally petty of me, but whenever Mrakas Gatley was mentioned, I kept reading he's called "Maracas" and giggling, which kinda spoils the page.