I had some mixed feelings on this book. I'll warn, I'm a hardcore sci-fi geek. I make no apologies for that. I think I went into this with my hopes perhaps a bit too high...not only over seeing a YA sci-fi amid the sea of paranormal, but to see a sci-fi by a female author. And on the whole, for a first book it wasn't bad. I just didn't find it to be particularly enjoyable or memorable, either. 
 The writing was stylized, but not in a way that I minded. And I appreciated the ongoing thread of 'Alice In Wonderland' references. I also liked the underlying concept of removing human will via scientific manipulation and historical revision. It was interesting to see the idea of 'progress' painted in such an ominous and morally thought-provoking light. In that way, more than anything I found it somewhat reminiscent of 'The Giver'. On the down side, the foreshadowing was more heavy-handed than tantalizing. And while there is, fortunately, a minor twist at the end, the murderer is obvious from very early on. 
 Ultimately, I found that I kept reading because I wanted to know what was happening and why, not because I particularly cared about the characters. 
 My primary problem was the lead female character, Amy. The girl starts out as irritatingly childish; her thought process and immaturity giving me more the sense of a 13 or 14-year-old rather than a 17-year-old with well-educated and influential parents. She progresses to becoming something of a whiny Nancy Drew figure, minus a good deal of basic common sense and self-preservation. I couldn't sympathize with her. As 'Alice', she takes entirely too long to accept that she's in Wonderland, and that her new reality has very different culture and rules. 
 On the up side, Elder was believable as a 16-year-old boy--from any time period. And Harley was a welcome side-character who's quirkiness was expressed well while avoiding the prevalent PC stereotype. The 'villain', however, wasn't as multidimensional as I would have liked. 
 As many have already mentioned, the cover of this book is misleading. It is not a romance. There are few romantic elements, actually...and while there is definitely sex that is portrayed in an animalistic (although oddly tedious) orgy-like fashion (including a fairly graphic sexual assault scene that I would have liked to have been warned about), it is all bluntly sexual rather than sensual. Not exactly what I was expecting from a YA novel, and not really my taste. But that's just my opinion. 
 I tend to agree with those who would prefer to think of this book as more Dystopian Fantasy than Sci-fi. There were just too many logistical problems that were driving me crazy. Are kids 250 years in the future really still abusing the word 'totally' as an adjective? And after a few centuries, why would there only have been four new slang/cuss words conceived? (Chutz, Brilly, Loons, and Frax being the sum of this vocabulary. I may be picking nits here, but it just felt like too much attention was drawn to their use.) But beyond the language, which I can overlook if I try hard enough, were things that forced me to suspend disbelief. 
 *Despite repeated mention of incest being a ship-wide problem, the artificial 'season' for mating is wild and unregulated. Genetic issues seem to be modified or resolved by a 'goo', which comes off as more magical than scientific. 
 *Why jettison bodies into space when everything else on the ship is so carefully and deliberately recycled? 
 *The big mystery on the ship seemed to revolve around attempts to fingerprint the murderer, which highlights an apparent lack of research over the manner in which fingerprints are formed (in the biological sense). Were it not such a pivotal plot point, it wouldn't have bothered me so much. But it's harder for me to pretend that anything speculative is feasible when points based on existing and determinable science are inaccurate. 
 As I've said, it wasn't poorly written, but I had the sense that this book was more of a flash-in-the-pan piece of pop literature than an enduring piece of timeless sci-fi. (Like, for instance, Ender's Game.)