So my opinion might be a bit different from some of the reviews that came before mine. I personally went into the book expecting it to be immediately better than Maze Runner (which was a bit of a slow starter, yet still a fabulous book), but felt myself a bit melancholy about the Gladers' new surroundings. 
 I wanted another Maze darnit! No, really. I have a Maze/Labrynth mini-obsession. It's how I ended up reading MR in the first place. 
 However, once I got past the initial "WTF IS GOING ON NOW?" moment, I settled into the story, ready to see where it would take me. The first half was good - and definitely not boring. Even so, I found myself putting the book down to read other things. The new environment just didn't hold the same appeal as the Maze/Glade idea did for me. 
 Once I hit about halfway, the book really started to hit its stride and I was suddenly invested. I wanted to know more about Brenda, the new character. I had to find out if Teresa was really good or bad. There were a few moments in there that had me second guessing my original theories, which is ALWAYS great in a book. Who wants to figure everything out from the start? Not me. 
 Of course, Mr. Dashner had to take me on another thrill ride, only to leave me wanting more. I'm no closer to having the answers in my hand then I was before. Give me book 3 now!