Shonen Jump announced that Funimation together with One Piece producer Toei Animation, Co. Ltd. publisher Shueisha, Inc. and broadcaster Fuji Television Network, Inc. have arranged to have One Piece animation broadcasted with English subtitles on One Piece official website.
The broadcasts will start on May 30th with episode 403, one hour after the episode has been aired in Japan, and will then be continued each week there after. At the same time Funimation will offer the series starting from episode 1.
Kanji Kazahaya, Director of Toei Animation had this to say about this next step:
"With digital technology drastically changing the media environment surrounding broadcasts, we've gained the understanding and cooperation of Shueisha, the publisher of the original manga, and Fuji Television, which broadcasts the show in Japan, the primary target audience. With help from FUNimation, our One Piece partner in North America, we've managed to make a One Piece simulcast a reality. With this simulcast, we'll be able to deliver a version of One Piece with much "fresher"　excitement and greatness than ever before to even more viewers in the United States than ever before. It's incredibly exciting."

Source: Shounen Jump


NEWS UPDATED ON 30th of June 2009.
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Today the Shonen Jump website announced that they, for the time being, will be closing down the service for the One Piece Simulcasting.This was cause by an unauthorized individual deliberately accessing the servers and posting the 403rd episode online. So as of this point, no episodes will be sent for an unknown time period.