spoilers:
I just saw the movie today. It was kind of a mixed bag for me. I enjoyed the performances and the plot was fine for a Terminator movie. I'm somewhat indifferent towards John being killed off because outside of Terminator 2 the character is more or less a McGuffin. So my feeling is if they want to move on to a new resistance leader so be it.

But Rev-9 was pretty dull as a villain, and Sarah's and T-800's inclusion in the plot was so forced that I feel it took away from the new characters, even if I enjoyed Linda Hamilton's return.

Overall I'd give it a C+. It probably is the best Terminator film since T2 but I don't know if that's really saying a whole lot.
end of spoilers