How come our heroes never at any point investigate who is sending the flowers every year ? Obviously it is someone involved with the case. As they are sent from around the world why not find out who on the island at the time of the disappearance would have had the opportunity to post them. Someone who was an airline stewardess for example ? As they were sent on a specific day each year it would have been piss-easy to work out whether she was in the place where they were sent from each time. Then Blomquist could have visited her, slept with her, and found out the truth.
Why was Harriet sending flowers anyway ? Surely it was common knowledge that he regarded them as taunting by the murderer - how come Anita/Celia never told her ?
How come Salnder chucks Harald's PC and diaries, which identify the murder victims, in the lake when at the end she tells Frode to watch the DVDs and "try" to work out who the murder victims are and send money to their families.
How come Blomquist's daughter (a clunking plot device if ever there was one) immediately interprets the six letter number codes as Biblical references when 1) No-one else over the past 25 years has done so and 2) No-one refers to biblical passgaes in that format anyway (do they ?)
For me the biggest mystery in this book was in the Vanger Family Tree on page 6. According to the dates, Birger's mother Ingrid was only 14 years old when she gave birth to Birger, a fact that neither of the acute investigators seemed to have noticed. It led me to the conclusion that this fact would prove highly significant to the plot, so I was rather disappointed when it was not even spotted!
I guess there are two sides to every story reading. I found this series of books one of the best I have ever read, I could barely put the last book of the three down and just wanted to keep on reading. The whole story just kept falling in to place - the more you read the more you got involved and the more you understood the loose ends. In summary - one man's book is another man's recycling. But we are all entitled to an opinion. Personally I wish he'd write some more.