Yeah that song fucking rocks. I fully admit that song is what got me interested in watching the series back in the day. Granted I liked GITS the movie when it first came out, but it wasn't a huge draw for me. Anime wasn't a big thing for me back then, still isn't a huge one. But that song, just fucking slick.2nd GIG had the better animation for its opening, but I find I preferred the song - Inner Universe - from series one of Stand Alone Complex.
Shame to learn that the singer died several years ago. I think from throat cancer? Cancer of some kind as I recall. She nailed that song though, hands down.
The tone of the song reminds me a lot of Paranoia Agent's opening theme song, as to why I like it. Fast drums/beat, high vocals, long harmonies. Just really nicely done structure for a song. It's got that fast, technoy beat that I love, but beautiful singing that works so well.