Board Thread:WARNING ALL USERS False Info\Spoilers/@comment-4091815-20140102223542/@comment-4091815-20140103221939

The quote is "Prepare to lose someone. We will possibly be changing our main title sequence. So - not everyone is going to make it out of this season alive."

http://teenwolf.wikia.com/wiki/User_blog:Paul.rea/Teen_Wolf_Season_3_Behind_the_Scenes_-_November#112413_.E2.80.93_DVD_Release_Panel_Video

He said it during a one on one interview at the DVD release event in November. The story, and a link to the youtube account with the video are in the November archives of the Teen Wolf Behind the Scenes page -