If Anime have a chance of getting a shot into American mainstream, Cartoon Network is the place.
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This was a hard one, but I picked Toonami. More people watch Toonami than Adult Swim, so I'd go with Toonami. However, Adult Swim, when it becomes more popular, can show more and more anime.
I'd say Adult Swim, mainly because they won't have to edit as much, if any.
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