Serebii does have connections of sorts: he knew all the english Diamond/Pearl Pokemon and attack names about a month before it came out in the US, and then some drama with another website person made him spill the info weeks before he was supposed to. He was even apparently afraid of legal actions and such, since apologized to any representatives in the update, heh...
Perhaps that legal fear is what is keeping his mouth mostly shut about all this. But since I believe him, I am happy and sad for two reasons:
1. We will indeed see a couple new characters tomorrow!
2. Say goodbye to Mewtwo. A few weeks back a moderator of serebii.net, LadyCelebi, posted on GFAQs that serebii Joe's sources indicated that Lucario surprisingly replaced Mewtwo from Melee. She talked about him saying that he "says he shouldnt know what he knows", and thats exactly what he said on that site...
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