Well Vampire knight for sure. I followed the serie from the start because I have a weakness for vampires but the story was so weak as well as the character development. I'm sorry but everybody who didn't see all of that coming is downright stupid.
Then we have Naruto of course wich speaks for himself. I do however like One piece and Bleach but both these series have the disease that too many shounen manga has and some shoujo. They are WAY too long. There is never a real ending. Enough already it's enough we don't want to make them a soap series!
In all most series are overated simply because people take them too serious. They are stories and that's all they are. They aren't real but the things they picture are and it's about the morals you should care not about the number of bishies (
Vampire knight
) I blame it on the hormones.