Now that I've had a little time to digest the film, I say it's a step down from the first, at least in terms of pure emotion.
The first had me tearing up in literally the first scene. Darkness never really got to me at all.
The main problem is that the emotional high-point of the movie is completely undercut by the obvious fact that they're just gonna save him and use Kahn's cells. I think it's a major, major flaw in the film.