The book is cover to cover references to geek culture from the late 20th century, and if you played RPGs /video games, and watched sci-fi/fantasy movies and/or Saturday morning cartoons, or read manga/watched anime, or enjoyed Monte Python, or anything related to any of that stuff, this book will keep you reading. I read it on the plane ride to and from Boston last week, so it was roughly a 14 hour read.
As you might be able to tell from that last paragraph, it touches on a lot of different things from that time, and has a little something for every geek out there. I won't spoil anything beyond what you can read on the back cover:
It takes place in 2044/45 mostly inside a virtual utopia known as the OASIS (it's an acronym, read the book to find out what it stands for), and the protagonist's quest to find the creator's hidden secret within the universe of the Oasis.
That description really doesn't do it justice, but trust me, you'll love it.
And there is a movie that is currently in post-production. You can watch the trailer here:
I watch the trailer, and there are really only a couple scenes and a handful of elements that I recognize from the book, which makes me a little sad. But Steven Spielberg is directing it, so I'm holding out a little hope that it will be well received. This article does make some some good arguments regarding it needing to be different/better than the book, but my primary fear is that it will lose its heart and core story in that transformation. But we'll have to wait and see.