Manipulative aliens in your mind...
Still, I believe that to get the most enjoyment out of it you have to be a fan of a particular set of science fictional tropes. If mysterious, super-powerful aliens who set up shop in people's heads and manipulate them to their own unfathomable purposes is your thing, you'll probably like this book. It is very much my thing, so this book was a feast for me. Extra points if the alien races have evocative, tantalizing names like Pattern Jugglers or Shrouders. Pattern Jugglers restructure your brain to make your thought patterns identical to those of another race. Shrouders... well, their function is more mysterious. You'll have to read the book to find out why they are called that.
I also like a coherent plot, where all subplots and threads come together in the end, everything happens for a reason, and all characters serve a purpose. "Revelation Space" is very tight in that respect. The tension did not let up throughout the book.
... which of them should you believe?
What kept me engaged with the story was that I didn't know until the very end which of the aliens could be trusted and which ones were to be feared. Actually, no: all of them were to be feared. None of them were really on the humanity's side. The only difference is whether they were willing to leave us alone, or not. It took me the length of the book to figure out who was plotting what against what. The human protagonists were just as confused as me. But unlike me, they had to figure stuff out while experiencing lethal attacks oh, about every five minutes! The aliens were none too gentle with the humans, shooting first and not even asking questions later.
As much as humans tried to puzzle out the intentions of their "puppetmasters", they still ended up mostly as puppets a lot of the time, though not for the lack of initiative. The characters were all very tough and smart, and did their best to play the game on their terms; however, intentions of superancient, superpowerful intelligences can be extremely difficult to fathom. In fact our characters got the only glimpse of those intentions when the superpowers decided to reveal some of the cards. The "puppetmasters" did that to convince their proteges to fight on their side, because apparently coercion alone didn't work as well. So we the readers find out the truth only from infodumps. Even then we can't possibly know whose infodump we can trust.
Tight plot, spectacular action
However, the convoluted plot in "Revelation Space" does not lead to frustration, but only makes the story more tantalizing. Probably because it hangs together by tight logic. I no longer take that for granted: I've read enough science fiction books lately where the vagaries of the plot betray the author's uncertainty of what the characters should do next. It made me more appreciative of books like "Revelation Space" where the plot seems very well thought out.
And even if it's a bit too twisted in some places, the action is so spectacular you can read this book purely for the visuals. :-) Very early into the book we find out how to kill a person using a spaceship flying at a near-relativistic speed as a weapon. No, it's not like using a nuclear missile to swat a fly. :-) The person to be killed is inside the spaceship. The murder is accomplished by placing the victim in an elevator shaft that goes along the length of the ship, and manipulating the physical characteristics of the flying ship to crush the victim. Quite impressive.
So -- mystery, intrigue, explosions, suspense, world-destroying weapons, the fate of the universe hanging by a thread, tough characters with posthuman enhancements (and 2 out of 3 main characters are women!) -- this book has it all. A very enjoyable, thrilling ride.