What's always attracted me to GITS, from the first movie on was the action and sci fi. I don't think of myself as an action fan, but when it's done with some originality, and the various twists that sci fi can provide, then I'm glued.
'Ghost hacking', being able to look up information in mid-gunplay, to get tactical data, and the risk of a seemingly harmless person actually being made of military grade hardware, sometimes with aerial acrobatic ability, makes for plenty of fun twists on ye olde "gunplay down a hallway" scanario.
Our star is of course, Major Matoko Kusanagi. Synthetic body aside, she seems to be one of the least interesting characters, on a personal level. This does mean however, that when they do slip a tiny bit of background on her, even the smallest thing feels like a big revelation. I suppose that's their plan. Being male, I'm not about to outright complain about her less than professional wardrobe, but it does take away from the 'reality' of it at times. I suppose if I had an idealized sythetic body, I might flaunt it too.
The other characters seem to be more fleshed out, more human.. (despite many of them only having a handful of human cells, inside a mechanical body) Batou, the mandatory 'big guy', is good natured, with a wry sense of humor that sometimes only shows itself with a smirk. Togusa is our 'everyman', with very few cybernetic upgrades, and a favoritism for an older firearm. It seems he's perhaps some kind of 'avatar' for the average viewer. While Batou is a seasoned ex mercenary, Togusa is fairly new to the ultra-high tech work, leaving him to be almost as new to many of the sci fi elements as the viewer, allowing things to be explained to us though his perceptions.
The main comic releif is supplied by the Tachikomas, a small fleet of VW-sized walking tanks, although they have much more impact on the story than just being cutely ignorant of things.
For me, one of the main failings of the show is the main stories, which span an entire season. They're filled with needless political and psychological mumbo jumbo, which one would think realistically, would be discussed in flatter terms... but if all your main characters have instant access to an encyclopedia in their heads, why should they wait up for us un-enhanced humans?
By contrast, for me the best episodes were those that had nothing to do with the main story. "Stand alone" episodes, you could say. Sometimes they show a single case, from start to finish, with a nice action sequence.. or maybe they explore one character a bit more, or in some cases, just tell a 'smaller' more emotional story.
If there's anyone who's seen the movies, but not these, be warned that this show ignores the events of the movies. Rationalize it any way you want..
And anyone who's read the manga, or played the old PS1 game will miss the cooler Fuchikomas... but the Tachikomas grow on you.... but I still want Fuchikomas.
The soundtrack sticks with me quite a bit on both seasons, (I'm halfway through season 2 at the time I write this) and both opening themes really stuck in my head.. by contrast, the closing themes didn't seem to fit the show, and were happily forgettable.
Ah, one last thing. Every episode is capped off in the end by a little short featuring the Tachkomas. They do some really random things, which often reflect on the events of the episode, but are sometimes truely random. They don't always seem to have a point, but in a way, that's part of the charm. They're doing their own thing after the show, and aren't particularly there to entertain you. Don't be surprised to expect a punchline, and get dumped off with a surreal "what??" feeling..
All in all, I'd have to say it's a must for anyone at all into sci-fi anime.. just smile and nod when they babble on too hard with the psycho-political stuff.