I think the "Big Twist" they are alluding to will be all about
connections.
There's a lot of opportunity to tie several characters together.
-Deb...........................could also be connected to anyone..Sister?
-Rita's Mom..................School Teacher. Could be something there.
-Christine's Mom...........The woman Arthur had a daughter with,Who was She?
-Dexter's Mom (Moser)...I don't think we know everything about her yet.
-Harry Morgan..............Could be linked to almost anyone.
-Frank Lundy................Again, We don't know enough about his history either.
-The C.I.'s...................Any one of Harry Morgans Informants may play a role.
I just pray that they don't end Season 4 Episode 12 with a massive "Cliff-Hanger"........Usually, Dexter Finales wrap things up with not too many loose ends left...just a lot of anticipation for the next season's premiere. I wouldn't be able to take waiting 7-8 Months for the resolution of a big Cliff Hanger.
BTW:
I agree with Hemi, The final scene in Episode 11 was amazing. Although, IMO....It's not "one of the best". I think it is
THE best scene out of all 47 Episodes of "Dexter".