There are a number of items inside the book that should remind readers of the game. For instance, in general when they mention someone’s weapon they mention the manufacturer (Alliance personnel generally use Hahne-Kedar weapons); and (almost) all the weapons mentioned are all found in the game (and are in fact likely weapons you picked up during the course of your play through).
The only weapon mentioned that was not in the game was the flashbang grenade, which to be fair, I wouldn’t have used even if it was (why throw a flashbang when you can throw something more explosive?). Omni-Tools were also brought up a few times in the book, but never by name.
The First Contact War is mentioned briefly, slightly more in depth than as was in the game. Saren, the antagonist of the video game, is also mentioned in the book and the mission that Anderson went on that was to prove him worthy of being a SPECTRE takes place in the book. We get to see how it really went (from both Saren and Anderson’s POV). We meet biotics (who are apparently a rare phenomenon; at this point there aren’t any natural human biotics), aliens (including the batarians, who we only found out about in the 1st DLC: Bringing Down the Sky), and the Council.
Commander Sheppard is not mentioned at all in this book, so if you were looking for some more info on him/her, this isn’t your book and it is doubtful there ever will be one, since you as the player pick his/her background. The next book, Mass Effect: Ascension, however does mention Commander Sheppard. It takes place post-Mass Effect and mentions the events that occur at the end of the game in vague enough terms that no matter what you chose it still makes sense.
In general, I think fans of the game will enjoy the book. It is a quick read and I thoroughly enjoyed it. I’m in the middle of the next one currently and it seems to be oriented on Cerberus (a pro-Human/anti-Alien criminal organization from the game, not the 3-headed dog) which seems to play a decent role in the upcoming Mass Effect 2.