To clarify, I must make two suggestions. The first is to be certain that you watch the four-part OVA, rather than the film (Polymatrix), as the latter leaves out enough material to be a disservice. And secondly - very importantly - do yourself a favour and watch it subbed. The dubbed version, as so often is the case, is languid and uninspired. The original Japanese language voice-actors did a very fine job and you will benefit from their efforts. I believe that between their very well characterised acting and Hiroyuki Namba's excellent original score, much of what may be perceived as deficiencies in the animation are more than made up for.
I won't be reviewing the plot here, as it is straightforward and much is written on it already. What I will say is that the story covers a number of very important and often divisive issues, namely how we treat the "other." In the best tradition of sci-fi we find androids used as a stand-in for the minority or immigrant population of your choice. "They're taking our jobs," "they're sub-human," "they're here for our use," and "they couldn't possibly produce great works on their own," etc. Not only is Armitage one of these minorities, both in fact and as analogue, but she is in addition a female. Doubly a second-class citizen! And yet imbued with indomitable character tempered with sensitivity, great power balanced with compassion. Ross, likewise, is a fantastic bridge between human (or white/male/majority) and android (non-white/female/minority), for despite his prior prejudices, he uses the best human qualities of reason, empathy - and ultimately - love, to guide his relationship with Armitage. In many ways the cop-buddy human/non-human pairing owes a lot to "Alien Nation" (1988) and "Mann & Machine" (1992). From the looks of it Armitage has likewise gone on to influence the upcoming "Almost Human" (2013).
A great many comparisons can also be made between Armitage and Ghost in the Shell, but here I will attempt brevity and say that while GITS is cerebral, Armitage is emotional. If GITS concerns itself with the nature of the soul, Armitage looks at what it means to have a heart. Despite all the similarities between the two franchises, in some ways they could not be more different. We accept Kusanagi Motoko as human because she is, though she often behaves more like a machine herself; while Naomi Armitage is not human at all, but behaves more like one than "the real thing." She embodies some of the quintessential essence at the core of the cyberpunk genre. What is it to be human? If you can't tell the difference, what's the difference? It is this last that, in my opinion, Armitage III examines perhaps better than any other work, on par with Bladerunner itself. One really can't give much higher praise than that.
