This book is located exactly between "I liked it" and "I really liked it" so it's a 3.5 for me. I liked Simon. I liked Blue. I like the depiction of Real Teens. I liked the friendships. I LOVED the humor. Just nothing stood out to me as AH-MAZING or even just "great". Overall enjoyable and a good read. 
 PS Blue was exactly who I thought he was based on a few important clues, although I admit I initially suspected another character. Blue = + :)