I've not seen the original Appleseed, but I've been told the two movies aren't connected at all. Still, not having seen the first meant that I had no idea what to expect for the second...
STORY - The sypnosis given on this website is crap (as is ANN's, since that's where it came from) and the information it highlights has little importance in the movie, Wikipedia's summary is a little better, though still lacking in proper details. I suppose those summaries are sub par in part because the movie's complexity, though. There are actually several smaller subplots interlinking throughout the Ex Machina, and the grand scheme the characters must overcome is not clarified until maybe halfway through. This makes for some interesting crossover between the substories, but it also means that someone who doesn't care for the subplots could become quickly disinterested before the main one locks into place.
Neither the substories nor the main story are particularly innovative though, probably because cybernetics, war, and mind control are such frequently visited themes within the sci-fi and cyberpunk genres. They're still entertaining enough, but there's definitely nothing profoundly new or deep here. The love story is cute, but lacking substance (I always dislike it when characters' love for each other is 100% pure and lacking in any uncertainties or doubts). The villain's motivation seems a bit contrived and the automation of a mechanized disaster a cop-out. It was disappointing mostly in that there seemed to be potential for a lot more material because the environment was set up so well, but none of it was ever realized.
CHARACTER - Ex Machina is another movie that falls into the trap of a full cast of generic characters. Deunan is a femme fatale that might be called a wannabe Motoko Kusanagi except that she's completely and utterly in love with Briareos, who himself is a typical tough guy cyborg. This relationship seems to force Deunan into a more typical "female" role, placing her in situations where she inevitably needs to be saved by her man and taking away from her otherwise badass persona. This might have been a decent way to put more depth in her character and I might be less irked about it if it weren't for the fact that Deunan seems to change completely depending on whether the scene calls for her to be badass or vulnerable, and there doesn't seem to be much of a thread connecting her two sides.
The entire character of Tereus and his subsequent subplot seemed pointless to me. While it seemed to toss a wrench in the canon relationship for a little bit, it didn't last long and ultimately amounted to nothing because Deunan and Briareos's love is pure and nothing can pry them apart! As a "bioroid," he wasn't supposed to have very many emotions, but he more or less acted the part of a normal human, albeit one with a flat personality. Everyone else was very much the same -- Athena was a typical suspicious leader-type, the commander was a typical commander, the villain was a typical mad scientist that you recognized at first sight even though you probably shouldn't have, and so on. But you know what bugged me the most? That one guy that always seemed willing to ignore all rules and protocol to help out our protagonists even though he had no clear motivation or reason to do so. Come on. That's just cheap.
ARTSTYLE & ANIMATION - Ex Machina was very beautifully animated in a style reminiscent of Final Fantasy: The Spirits Within. The use of motion capture made the characters' movements realistic and smooth, and the highly rendered environments made sure that they fit in their surroundings. The mecha designs were unique and fun too. A few of the special effects (such as explosions) could have probably looked better, but in general, the movie was very pleasing to the eye. (Don't forget to keep an eye out for your John Woo doves!)
MUSIC - It's a pretty score, but nothing particularly noteworthy.
VOICE ACTING - I saw this movie dubbed, and I must say, it was a pretty darn good dub. The voices were appropriate (if not typecasted), anyway, and with so many Greek-themed names like Briareos and Athena, pronunciations were likely much more accurate than they were in the original. Wikipedia also notes that the movie's forward is more detailed in the English release.
OVERALL - Ex Machina wasn't a bad movie. As a cyberpunk fan, the story was alright enough, if a little lacking in originality. The characters could have definitely been better, but if nothing else, they were on par with the story's sophistication. The animation was probably its strongest point, but it was good enough that it may be worth a watch just for that.