IG and CLAMP definitely had the potential to turn this trainwreck of a series around for the better. The finished product? Nothing but bitter disappointment about how a great piece, Blood: The Last Vampire, could be turned into this.
The issues definitely begin in the characterisation. Nobody is interesting. There is no emotional attachment to any of the struggles they go through, and we 'care' because the movie tells us to. Fumito definitely had the potential to be a remotely decent villain, but even there we are let down.
The animation is mixed, but overall it is fairly negative. Much similar to the series Blood-C, the
majority of art enjoyment comes from the monster design - and while a lot of what appeared is clearly rehashed from Blood+ and the entire Blood series (if you dare group them together), it is still the high point. For the remainder of the scenes, the animation is carefully guised to look pretty with that distinct I.G. style, but with some inspection the flaws are gaping. The CGI scene? Lets not go there.
The plot itself made no real sense. The concept was clear, but the whys and hows of it were significantly lacking. There is no resolution, or even understanding, of the events that transpire and why we should be interested in them. Watanuki appears simply as CLAMP fanservice, in a drawn-out sequence which was really unnecessary.
Blood-C has concluded to be a trainwreck of a project. With I.G. having input, one would have hoped for a return to the glory days of Blood: The Last Vampire. However the final project is nothing short of ridiculous, and while it is a definite improvement from the series it is still not cutting remotely close to average.