I suppose I wanted to like it when I started out. I don't dislike it, but the whole thing felt kind of bland. 
 I did quite like it for the first hundred pages or so at least, but then for whatever reason it just seemed to stagnate. I really liked the worldbuilding, I really liked the concept, and, of course, Oliver's writing style is a dream to read, but I really just wasn't interested in the end. 
 Mild spoilers ahead, depending on what you define as a spoiler in regards to a story about love. 
 I didn't find myself rooting for the protagonist at all. Lena is the typical 'nothing special', and Alex is basically a block of polystyrene, so did I care about their relationship? Nah. This really surprised me, too; I adored the characters in Oliver's other novel, Before I Fall, specifically Sam and Kent. They felt real, tangible, motivated and loveable. The two in Delirium are frankly forgettable, which I was really disappointed by - if you clearly can write characters like Sam and Kent who are relatable and realistic, then why would you choose not to? Was this a way to get the reader adjusted to the dystopian society? The average relatable girl to provide a gateway into the world so the audience isn't too overwhelmed? I just can't think of any good reasoning for that. Was the whole thing a metaphor for same sex marriage rights, what with the limitations on love and such? Was I wrong in focussing on the characters when I should have been looking at the metaphor? Or was Lena's submissiveness just a quick and easy road for (view spoiler)[lazy (hide spoiler)] character development? 
 Despite all of that, not a bad book at all; it definitely has its moments. If you're interested in the premise, or if you haven't had your fill of dystopias just yet, then go right ahead and read it. Three and a quarter stars.