If I'm reading this correctly...I'd like to point out that you're basically saying, "if WFT was leaked in advance and then revealed, I'd believe it more." That's pretty much what happened, just in a shorter time period than you probably wanted, and time is irrelevant to the leak's legitimacy.
Maybe i poorly explained myself, so I'll do it alittle better right now:
To say i should believe a leak because he had gotten 3 out of the 6 claims correct (5 of which were heavilty requested characters that made up many predictions and fan rosters) is silly. Everyone believes the leak because of the devasting prediction of the WFT and how 'nobody in there right mind could have guessed her.' (And also because the supposed leaker got her name right).
Smashboards, GameFaqs, the people who visit these sites and stay in the loop, make rosters, and so on, are a small minority of the broad spectrum of people who keep up with this game, not to mention the casuals. I decided to go see if my thoughts were true about where Wii Fit stood as a top seller to support my claims. I believe it is Number Six, trumped by (ofcourse) Mario and Wii Sports games.
http://en.wikipedia.org/wiki/List_of_best-selling_Wii_video_games
If this person wanted to make an accurate prediction, he/she would not look from the eyes of a fanboy, fanbase or gamer, but from a developer wanting to make a game with iconic characters that represent Nintendos history while trying to please his fanbase at the same time. Mii and WFT resemble characters from popular wii games that have become iconic (WFT pending) and at the end of the Wiis cycle, they kind of made the Wii the success it was. Little Mac and an Animal Crossing rep made up many prediction rosters list since before Brawl (and from research, even Melee), not to mention they are indeed important to Nintendo and are iconic. Pac-Man stems from Namcos development of the game, to also add to the believability factor, and how at that time in early 2013 Pac-Man as a newcomer on prediction lists was becoming a bigger trend. And come on - Megaman? That's been a gamers wet dream since the 90's.
Now, say in an alternate universe, that instead of WFT Nintendo gave us Little Mac at E3 2013. We would not even be on this thread right now, would we? If this leaker is indeed a leaker we would skim over him and his ridiculous claim - A WFT? Crazy. The worst part is if he is indeed a leaker and the WFT was instead revealed a month before the game hit stores, we wouldn't have even heard of him, unless he kept coming around trying to prove that he knew about these six newcomers, which admittedly wouldn't be very smart of a leaker to do. What I'm getting at is there may never be a way to know if it is true or not, we can only debate it.
Perhaps with the feelings of disbelief and awe that came with the WFTs reveal many also were willing to believe anything at that point. I never once said that this isn't a leak, it could very well be, but I'm choosing to withhold judgement until more evidence presents itself. This could very well be a true leaker from Namco-Bandai (even though in the initial post they state that it is their 'unlikely prediction') or could be one of the hundreds of fans predictions that, for once, was actually RIGHT! It's not out of the realm of possibility for either to be true.
So, BKupa, that's what I mean if WFT came a bit later instead of at e3. Just as we all would think that if say someone came to us before the VGX (and there was no boxart, just as a hypothetical) and said that Reggie will announce Cranky Kong as a playable character in DKCTF, they must know something. People even saw the boxart and didn't think Cranky was playable.
So, all in all, we'll just have to wait and see. I don't like how people are saying that the other three will be revealed at the next E3 either, but if you want to believe it, go ahead. Being skeptical is just natural for me.
(I just noticed above that Fenrir made the same points I did, and I didn't even look at his until I wrote this little paragraph. So Idk if that's an oopsy daisy or that someones on the same page as me.)