The story
MangaGamer was originally envisioned as a company that would sell Japanese visual novels overseas by Hiroshi Takeuchi, also known under his alias Bamboo, president of Japanese eroge development company Overdrive. Due to the cost involved, he convinced several other Japanese eroge companies (Tarte, Nexton and Circus) to take part in a joint venture.
Due to this setup, the initial lineup of titles consisted of titles produced by companies involved in MangaGamer's creation, with Navel soon joining with their first title, Shuffle!. These early titles were translated by native Japanese speakers involved with parent companies, which resulted in a subpar quality.
After complaints from fans, it was announced that a complete re-translation of Edelweiss was in progress. Starting with Soul Link, translation and editing is handled by an international team of native English speakers, resulting in an increased quality. The company itself is headed by a relative of Takeuchi, and a core Japanese staff is spread between the involved Japanese companies.
At their panel at Otakon 2011, MangaGamer announced that they are expanding their business into digital distribution of erotic manga (by Japanese publisher Akane Shinsha) and anime (by Discovery).
From Wikipedia’s article on MangaGamer, shared under CC BY-SA 4.0.4