I didn't start reading an Aliens novel with real high expectations, and I got pretty much what I expected. I haven't read the comics upon which this book is based, so I can't tell if it's an accurate adaptation, but it was an ok story.
The cover of this book is really cool; it's what led me to pick it up in the first place. Unfortunately, it's the best part of the book. As soon as you open the novel, you see that this is not Steve Perry in his best form. He constantly plugs in commas where semi-colons would be much more appropriate, and neglects to put commas where they should be, which makes many sentences read quite awkwardly. He uses very short paragraphs, often jumping from thing to thing without really going into them. This book could've gotten another star just for being well-edited.
The backstory of the characters is exactly the same as the story of Aliens -- a squad of Colonial marines goes to Rim to investigate something, finds the aliens, nukes the colony (it's the only way to be sure), and there are only 2 survivors -- a marine corporal and a civilian girl. Turns out, thought, that the girls parents started the alien problem when they discovered a giant, horseshoe shaped derelict spacecraft and went to investigate...sound familiar?
Also, this book spans nearly three years, most of it at the end. There are a ton of characters, multiple plotlines evolving at once. It's just too short. With another hundred or two pages, we could've gotten to know the characters, instead of just observing their actions; the neatest sequence in the book, the alien takeover, could've been shown in a lot more depth.
Overall, this story is a semi-entertaining, somewhat well-written contribution to the Aliens saga, but it could've been much better.