A very dark sci-fi anime by the Serial Experiments Lain crew. The biggest names from Lain would probably be Yoshitoshi ABe on original character design, Ueda Yasuyuki producing, and Chiaki Konaka writing. Also, Shigeo Akahori, animation supervisor on Metropolis, is also involved with the character design. The only other namedropping I'll do is to say that Hajime Mizoguchi did the music for Escaflowne with Yoko Kanno. Here are the most complete and accurate production credits I could find:

Director: Hirotsugu Hamasaki
Series Story Editor & Scenario: Chiaki Konaka
Character Conceptual Design: Yoshitoshi ABe
Character Design & Chief Animation Director: Shigeo Akahori
Art Director: Hidetoshi Kaneko
Technical Director: Takuji Endo
Concept Design: Gota Nanami
Graphic Design: Norihiko Nezu
Texhnolyze Design: Kaihei Hayano
Mechanical Design: Morifumi Naka, Toshihiro Nakajima
Color Design: Yuko Kobari
Music: Keishi Urata, Hajime Mizoguchi
Producer: Yasuyuki Ueda
Production Studio: Madhouse
Original: Rondo Robe

The opening theme, "Guardian Angel," is by Juno Reactor, and the closing theme, Tsuki no Uta, is by Gackt.

This anime is very much an acquired taste. It is both visually and thematically very dark, and seems rather confusing through much of the show. The creators had the audacity to make the first episode the most confusing of any of them, and getting progressively less confusing from there. Some of the most adult themes I have ever encountered in anime are present here, including multiple episodes of prostitution, and parental sexual abuse. There's also a lot of violence, but neither the sex or violence are intended to be exciting or titillating - it's just a very gritty world these characters inhabit, life is cheap and people get their rocks off however they must.

The name Texhnolyze comes from the name given to the cybernetic prosthetics technology prevalent in the show. Indeed, as Lain seemed to center around the Internet, Texhnolyze uses cybernetic prostheses as its basis. While Lain essentially focused entirely on Lain herself, Texhnolyze has a large cast, and at many times could be described as a political drama. Character development is not sacrificed, however - the characters are some of the most complex and dynamic of any anime I've seen. The visual style is much more down-to-earth than Lain, but still rather arty - there are long, lingering shots of scenery and people's faces, dialogue goes on while the camera investigates a fishbowl, and so forth. This occasionally makes the pacing seem slow, and it is, but it complements Konaka's minimalist writing well. The sound is also done very well and is practically the centerpiece of the first episode - not a single line is uttered until twenty minutes in, as swirling fan blades and buzzing fluorescent lights set the tone.

Minor spoilers ahead - if you're like me, much of the enjoyment comes from deciphering the plot for yourself, in which case you shouldn't read any further. I confess that I have only seen the first 16 episodes, since the rest haven't been fansubbed yet (cough, cough). If it is necessary to amend any of this w/u when I have seen the rest of the show, I will do so, but this is intended as a introduction to the story and not an analysis of the story; most of this information comes from the first 4 or 5 episodes.

Synopsis: The city of Lux seems to be going for the Dystopia of the Year award. It is implied strongly that the city itself is housed in a giant underground structure, but there is little visual evidence of this - the environment obviously has skies and horizons, even large barren wastelands. The only reason it appears to exist is that it is home to the world's only Lafia mine. Lafia is a moss with semimagical properties that is necessary to prevent the human body from rejecting the Texhnolyze implants. High technology apart from Texhnolyze is mostly absent from Lux, although probably not from the whole world. Much of the show focuses on the various factions fighting for control in Lux, somewhat like the fight over Arrakis in Dune.

Major organizations and characters (with seiyuu in parentheses)
The Class are not citizens of Lux, but rather live above the city somewhere in the sky (or on the surface of Earth, which could still be above Lux). They are only alluded to in the early part of the story, never seen, and their purpose is fleshed out as the story progresses. Two members of the Class have come to Lux for their own purposes. One is Yoshii Kazuo (Inoue Takashi), A man who descends from the heights to Lux early in the story. He obviously has considerable martial ability, but his motives are obscured. He doesn't appear to be operating under anyone's orders, and at times it seems he is a one-man independent faction. The other ex-Class member is Kaneda Eriko (Niki Shizumi), commonly called "Doc" by other characters. She is the most skilled Texhnolyze surgeon in Lux, and the privileged employ her as necessary. Again, why she left the Class is unclear, but she has lived in Lux for some time. She seems to desire to advance the state of Texhnolyze technology, and so needs a regular supply of test subjects. Like Yoshii, she prefers to remain independent of any other organization, using her own considerable resources and abilities as she sees fit. Organ is the closest thing Lux has to a government, although their primary claim to power is that they control the Lafia mine. They are structured much like yakuza, and maintain large groups of heavily armed thugs. They are unequivocally pro-Texhnolyze, and their members enjoy its benefits. Oonishi Kyogo (Tsuchida Hiroshi) is the on-again, off-again leader of Organ. His benevolence angers many of the lesser Organ warlords, who would rather rule through violence. His legs have been Texhnolyzed, and he claims that this gives him the ability to hear "the voice of the city." The Disaster Relief Alliance, usually simply called the Alliance, is the most vehement anti-Texhnolyze faction, believing that such technology sullies the human body. They are considered to be something of a religious cult, and are the primary enemy of Organ. They are led by a rather stoic Kimata Motoharu(Nakata Jouji), who is not a major character. Lakan is essentially a youthful biker gang. They seem to survive by running a protection racket, and they are indifferent towards Texhnolyze - many (if not all) of their number have received Texhnolyze implants, probably by Doc, since they couldn't pay for it otherwise. They are led by the charismatic Shinji (Kitade Masaya), who is adept beyond his years at political maneuvering . The people of Gabe do not live in Lux proper, but rather in a separate but geographically nearby town. They left Lux generations ago, apparently sick of the strife there. They are led by a council of elders that is itself guided by Ran (Itou Shizuka), a young girl who can see the future. She dislikes her role as prophetess of Gabe, but she can do little about it.

Thrust into this milieu is the main character, Ichise (Haga Akira). His father was hanged ten years earlier in somewhat mysterious circumstances, and his mother died shortly thereafter; his only keepsake of his childhood is a few cells of his mother suspended in a jar of fluid. He has lived in Lux all his life, apparently, and when we meet him he is living in squalor, paying the bills by boxing and prostituting himself. He is a strikingly angry young man who views violence as his primary means of communication. Like most lower class citizens, he is against Texhnolyze on general principle, but will not sacrifice his freedom to join the Alliance. When he gets maimed by some vengeful members of Organ, he is Texhnolyzed against his will by Doc, and the events of the story are set in motion.

Spelling of Japanese names in romanji gets a little inconsistent, so what you see here may not be what you see somewhere else. You have been warned.

References:
watching the show
http://www.cjas.org/~leng/texhnolyze.htm
http://www.animenfo.com
http://scac.prohosting.com/anime-caravan/s-texhnolyze.htm