The Very Short Introduction series are written by professors of the subject and are aimed at provoking cross-discipline intrigue in the reader that may incite further investigation and reading - and boy are they good at achieving exactly that; often they leave more questions than answers.
Planets details the solar system in general, then spends the majority (41/125 pages) talking about planets like Earth (Rocky Planets) before detailing the gas giants, satellites, rings, asteroids and trans-Neptunian objects (TNOs) - the description of which are largely factual, with some postulation on the exact composition and formation that arise from each of the widely varied bodies.
I personally found the composition & formation of the gas giant's satellites the most interesting, referencing the missions that got us the data we have today, Europa, Io and Triton are intriguing places. It also deals with the whole Pluto classification furore. Rothery then finishes on the most intriguing thought of all; the question of life in the universe.
A deeply fascinating book, as well suited to the amateur astronomer as the professors as a quick reference book. Jam-packed with statistics and black & white photos of the planets/satellites/asteroids in question. Highly recommended!