I'll be your Huckleberry!
Oh...Dexter will be back next season. Indeed, it was not the ending I was expecting. It was definitely a story line that came full circle. What will be interesting to see is how will Dexter respond? Will he follow in the same footsteps as his own father and mentor and teach his own boy to follow the code and be another Dexter.
I guess that would depend on the Psyche development of the child and what dark personality traits may emerge as he grows.
Personally, I think the child would be to young to remember anything that occurred, but having Dexter as a father, he could easily be raised by a loving, caring and supportive father or a loving, caring and supportive, on going serial killer. He has proven throughout the series, he can maintain both roles.