If anyone is familiar with the Bookburners serial then you know that it's remarkably similar to The Invisible Library series. I really like the Bookburners serial so I was excited to come across something else comparable.
I enjoyed The Invisible Library too and really can't believe I waited so long to read it, but one thing I thought could have been better was the world building. It just wasn't as defined as I would have liked it, and I'm referring more so to the Chaos concept, the alternate realities, the Library Language even some of the characters and their abilities were underdeveloped.
I realize it's a pretty complex system but there were a couple of times I wondered if the author even knew where she was trying to go with it. Maybe those loose ends are tied up in the next book but, I personally like for the foundation to be laid out and nicely detailed, right from the start. It drives me nuts when authors use future installments to fill in gaps and missing pieces.
I am intrigued by the Library though and I really like Kai, Irene and Vale so I'm definitely going to continue the series with hopes that the many underlying layers of the Library develop into something a little more cohesive.