With Ready Player One coming out in the theatres I tried Cline's next novel, Armada. Don't bother with it - it isn't nearly as good (IMO of course).
It posits that the Earth is going to be invaded by aliens, this was discovered in the 80's, and ever since there's been a hidden secret government conspiracy to prepare humanity for the invasion by getting movies made (e.g., Star Trek, Star Wars, Aliens, etc.) and videogames that involve fighting space and land battles.
And the reason for this post: CR himself gets namechecked twice as one of a small set of brilliant video game designers who are recruited as part of this government operation to produce a exact simulation of space warfare as an MMO so that players, thinking they're just moving up in the ranks of an exciting BDSSE, are actually being trained to be spaceship drone operators to protect the human race when the inevitable alien invasion is finally launched. SC is specifically mentioned as a forerunner of this MMO, Armada, because of its fantastic fidelity.
Anyway, even without these tiny little tidbits the book isn't nearly as good as Ready Player One. This is just the icing on the cake, so to speak.