Anime Translation
With the recent dubbing of Sailor Moon S and the inevitable censoring of Tenchi Muyo!, I've heard much complaining from fans of these shows about how "Such-and-such Company is ruining the show!" They complain how the translation is far from perfect and cuts are being made to the show. Let me make one thing clear before I go on:

Differences in languages is brought on by differences in cultures, opinions and ideas. Whenever something is translated, it loses some of its original meaning. It is impossible to replicate everything that writing contains. In the case of Anime, much is lost in the transition to English. It's unavoidable. Before any cuts or changes in a translated script are made, the show is already far different from the original.

Fansubs
Dubbing corporations hate it, and so-called Otakus swear by it. It's called a perfect translation. That's far from the truth. Fansubs fall prey to the same problems as all other translated materials, and then some.
A traditional fansub is created like this...
1. Episode of show taped off TV in Japan. (Or video of episode of movie is bought.)
2. A fan of the series, who, more or less knows Japanese, watches the episode and translates what they hear.
3. Using video equipment, the translated text is added to the existing video track, keeping the original sound track intact.

Although fansubs retain the original soundtrack, by their very nature, fansubs are of much lower quality then professional subs or professional dubs. Most fansubbers are in the "business" for the love of the Anime show. They want other people to be able to see the show and enjoy it. Sometimes liberties are taken with the script and some lines added or taken out, making it slightly, or even radically different from the original Japanese script. If a certain series has been subbed by more than one fansubber, differences like character name spellings and pronunciations can show up. A well known fact of those who own fansubs is the video quality is incredibly awful. At the very minimum, a buyable fansub tape is fourth generation. Most are dozens more than that. After a few generations, colors begin to bleed and the image begins to flicker and the subtitles become unreadable at times. I bought a fansub of DBZ Movie #12 and it was completely unwatchable. After 5 minutes into the movie, every other frame was pure static. The first 5 minutes didn't look that hot either.

Cultural Differences
For an Anime show to be accepted and successful in America, it needs to go through a little more then a language change. The differences of culture between America and Japan could make some segments and ideas from the show either unacceptable or confusing for general American audiences. Here are a few examples.

Many shows brought to America have references to homosexuality hidden or even cut out entirely. Japan has a much more tolerant stance on homosexuality. Even though many advances have been made, America still has a very homophobic culture. "Gay" has become a derogatory term. The thought of a sexual orientation that is "not normal" leaves many people uneasy. Shows that openly discussed homosexuality, such as "Ellen" had their viewerbase and ratings drop drastically after the first mention of the main character being gay. It has gotten so out of hand that a character from a children's television show has been accused of being gay mainly for his purple appearance and triangle on his head.

Violence is a common occurance in some Anime shows. Dragon Ball Z is the most mainstream American example. Although violence is everywhere on American TV, it has never been looked very kindly to on childrens television, especially now that it's being used as a scapegoat for mentally unstable teens shooting up their schools. Any excessive violence must be cut or painted over to be suitable for overprotective parents. References to dying is frequently covered up by calling it things like "passing into the next dimension" like it was done to Dragon Ball Z.

Discussing or even referring to sex is something that cannot be done in children's programming. Especially since most children in America are taught that their "private parts" are "naughty". When censored for the American audience, old men in Anime shows who were perverts in Japan become tame, "made love" gets changed to "in love", and so on and so on.

The Dubber's Mentality
Fans of these shows who were first introduced to the show through Japanese TV or fansubs might look at the dubbed version and think that it's awful and nothing like the original. They so much as look at the dub and feel like vomiting. They bitch to the dubbing company and on message boards how the show sucks. These people don't undersatnd what the dubbing companies are doing:

Most dubbed Anime is meant to be watched by, and only by kids. Not by teens and college students who watch fansubs. Dragon Ball Z, for example, was aimed at preteen boys in Japan, and it's also aimed for preteen boys in America. It was never meant for anyone older. The key demographic remains the same.

To be finished...um...later.