hmmm...these are all really interesting ideas. I think Dana is alive and Zack and Julie will go looking for her and find all kinds of trouble, and I think Julie's mom helped them put Dana up for adoption or something, or that Mike is really Dana's father...all just ideas.
I love the show, and think Bree has a major stalker on her hands...I think it will bring she and Rex back together, and bond them again. I think he will save her life and they will be even so she will forgive the affair, etc.
Those are my theories....I even got my husband hooked on the show, although he won't admit it. He just "tells" me when it is on "Honey, your show is starting..." and then watches it with me. He loves Gabrielle (of course what man wouldn't?)....