The first film was fantastic, and the second often unfairly criticised. The action scenes were spectacular, and the plot decent enough to set the trilogy up for a decent finale. It's just a shame that the third film was lacking in every department, really.

I'd give the trilogy a B overall, since as a single story it's reasonably enjoyable. Factor in the Animatrix backstory with that and it's a good series, with the good outnumbering the bad to create a watchable product.