I love Ghost in the Shell. There's just something about the whole idea behind it that I think has so much potential. The idea that every part of you can be replaced with cybernetic prosthesis -- while not exactly original -- is cool enough. But add to that the fact that even your brain can be cyberized and linked directly to the internet brings up all kinds of opportunity for cool storylines, from the technical (ie, brain hacking), to the philosophical (ie, what remains to identify you as human?).
The original manga was written/drawn by Masamune Shirow, who also acted as a consultant on this first season of the Ghost in the Shell: Stand Alone Complex TV series. And if you've ever read the manga you'll notice his influence right from the first episode by the intricately complex plot and engenious use of contrived-but-plausible technological concepts. Those are two things that I just love about any anime because it forces me to think in order to keep up with what is going on, but at the same time is interesting and cool enough to make me want to do that extra mental processing. To me, that just makes the show that much more engaging.
Though, to be perfectly honest, there were points where I was a little lost in the web of political positioning, conspiricies, and character motivations that made up the show. But even at those points, the show never stopped being entertaining due in no small part to Production IG's awesome-as-always animation quality. That coupled with Yoko Kanno's creative and emotional soundtrack gave the show a whole other layer of quality.
The end of the show did seem kind of unexpectantly anticlimactic in a way, but at the same time it was not disappointing and was very enjoyable and satisfying. But anyone expecting a all-out cybernetic brawl will probably be very surprised by how it all turns out.
The only thing that did bug me about the show was the way the episodes were structured. There were "complex" episodes, which involved an overarching storying, and then there were "stand alone" episodes which took place totally removed from the larger story and from each other. Although the episodes themselves were great, you could never tell when you were going to get back to the complex episodes. At first it seemed that there would be a regular pattern (like three standalone, then two complex), but at times you would have long stretches of one or the other. I just wished it was more prectible. But that's really only a relatively minor point and I could even see understand some arguments for doing it the way they did. Regardless it's a small price to pay when everything else is so great.
Overall, I'd recommend the series to anyone, whether or not you are into animation. The intricate plots alone I think are enough to capture people's attention. But the animation and music together with the awesome story -- to me -- make it anime's perfect storm.