Funimation are going to release the series in thirteen episode batches, Its still unstated whether they are going to be starting at episode 1 or episode 144, I would put my bets on the latter. VIZ seem tight to keep a hold of the episodes prior to that because they are very much crap with things other than the holy grail that is Naruto and its shadow Bleach.
So.. The only way to genuinely watch One Piece is to wait for these, or watch the fansubs. I doubt we'll see the Funimation dub on TV over here, Our Cartoon Network seems to dislike anything like anime and sticks it on other channels that really are kinda ******, The chances I would imagine is for it to go over to Jetix. Still slim though. Toonami had the 4Kids dub back in the day, I doubt CNTwo or anything would start airing it again. I don't think it was getting the ratings it needed.
Also, Interesting fact. FUNimation's One Piece is getting much much higher ratings in the states than the 4Kids version ever did.