Authors often feel compelled to tell the same story again and again. Sometimes literally the same story, from a different viewpoint (as in Orson Scott Card's Ender's Shadow). More often, it's the same plot dressed up with different characters (as in L.E. Modesitt's Recluce series, or almost anything by K.J. Parker). I don't necessarily object to that approach - I keep buying Parker's stories as they appear, and I like them all; I bought the entire Recluce series in e-form when it was on sale recently.
If you're going to tell the same story, though, you have to somehow make it new. Peter Hamilton treads pretty close to the edge in this book. If you read his Void trilogy, you'll recall Edeard, the young man from the country who gathers power to fight against injustice in the big city. In Abyss, we have Slvasta, a young man from the country who gathers power to fight against injustice in the big city.
It's impossible to believe that Hamilton didn't recognize the similarities; Edeard is specifically referred to here - Nigel has experienced all of the dreams about him. Yet Hamilton offers no real comment, no nod to the fact that he's covered this ground before. To be fair, the details have changed - Edeard gathered telekinetic power, while Slvasta aims for political power - and the hidden powers are quite different. But the foreground characters and the society are very similar. For much of the book, I wondered what Hamilton was trying to show us, other than that power corrupts.
Similarity aside, the book is entertaining and well written. It focuses mostly on the Void (the strength of the Void trilogy), and far less on the Commonwealth (the Void trilogy's weakness). The story is interesting, the characters appealing. The philosophy is pretty straightforward (much as in Modesitt's Recluce books, good and bad are clearcut), which is attractive on a small scale, but works less well as the book goes on. Hamilton introduces some difficult moral decisions, but then decides to pass them by rather than actually examining them.
Hamilton seems to assume (probably correctly) that most people will have already read the Void series - he provides a the key background filler, but when his characters enter the Void, they figure out its properties with remarkable speed. Some other insta-knowledge is equally off-putting, but is clarified later in the book. Hamilton does get carried away with some minor jokes that feel out of place ("comrade", "sheriff procedurals"). Some of the pseudo-science could do with a little more handwaving (enzyme-bonded concrete made out of ... pretty much anything? what is that?). There are one or two strange cultural errors (tacos as a no-crumb space food? maybe he means burritos). Some key decisions in the book (e.g., a trip by Slvasta) seem highly unlikely, and weaken the story. I give Hamilton credit for trying to introduce some racial variety, but it doesn't quite work out. For one thing, skin color is never noted unless it's black. For another, the planet was populated by a very small group; after many generations, the population is likely fairly homogenous.
All in all, a decent start to a new duology. Despite the disappointing conclusion of the Void trilogy, Hamilton has maintained enough interest in the Void that I could see reading the second book of this set - in part because it promises to escape the "Edeard Take Two" structure of this book. If you haven't read any Commonwealth or Void stories before, you'll be fine with this and should enjoy it. If you've read the Void trilogy and want more of the (very much) same, this is it. If you were only mildly interested in the Void, or if you're looking for something startling or original, look elsewhere.