Just a quick note regarding the Petill leak: We'll know if this guy can be taken at all with a grain of salt by Friday's Pic of the Day (at the latest). And even then, he'd still have to guess correctly about King K. Rool, a Gangplank Galleon Stage, Lucas getting cut, Shulk making it in, and Mewtwo coming back. I'd put a check too over his second part of his prediction, but needless to say, he's probably going to be right about all the characters he mentioned anyways.
With all that said, let's tackle the gematsu leak. Now, before I begin, I must reiterate: I have nothing against either his predictions or his unconfirmed characters. If nothing else, I've been lobbying for all of them for quite some time now (not so much Chorus Men or Greninja, but I'll get to that later). Yes, I am even one of those rare few people that predicted Wii Fit Trainer. Sue me. In fact, if nothing else, one can easily view the gematsu leak as a whole, at the very least, as a guide post on what to expect in regards to newcomers. I do not, however, consider it a real leak but a series of well-educated guesses, and I'll tackle each of these head-on.
First thing I'm going to do is go over all the newcomers as of right now, and bring up brief counter arguments as to how this guy predicted each and every one of these characters. And just to be cheeky, I'll reveal them all in the order in which said characters were revealed:
Villager: While not exactly a character everybody was asking for, given the large copious amounts of Animal Crossing content in Super Smash Brothers Brawl (to the point where Animal Crossing had its own section of trophies, stickers, a stage, and yes, even a symbol, but no playable characters), it was only expected that we'd get either the Villager or Tom Nook. The first hint that may suggest that this leak may be fake is the fact that he was called 'Animal Crossing Guy' instead. His Japanese name would have translated directly into Villager anyways, and using the "can't read Japanese" argument will prove contradictory later on.
Mega Man: While being third party would not have guaranteed his presence in the game anyways, even with the large fan demand for his inclusion, the biggest hint that he was most likely going to be playable was due to the fact that, when asked by a fan regarding a child Link returning, Sakurai answered that the entire roster wasn't fleshed out yet, and that he didn't know if a Capcom character would be playable or not. Now granted, it could have been just about any Capcom star, but as far as third party representatives go, the most likely would be a studio's mascot. Who's the mascot of Capcom? None other than Mega Man himself. However, this is just a deduction technique; truth be told, nothing here indicates fake leak whatsoever.
Wii Fit Trainer: This is the one character that people give credit for in regards to the gematsu leak's credibility, and thus the one thing (along with his track record) that gives him so much credibility in the first place. But similar to the Villager, one has to examine the character from the point of view of what is successful and what would make perfect sense regarding Nintendo first party IPs, and guess what? Both the Miis and Wii Fit fit that bill, especially regarding recent IPs. Even if you did not expect or want the character because you were thinking of appropriate Nintendo characters for a fighting game, it'd only make sense to represent the best of Nintendo's history through a character like Wii Fit Trainer. Add on top of that "a character nobody expects to see," and Wii Fit Trainer became the most likely candidate to fill this void. Granted, this may have taken some amazing deductive reasoning, because aside from myself, I didn't know anybody who could have saw Wii Fit Trainer playable coming. But as of right now, this is the only truly valid point in the leaker's favor in credibility.
Rosalina & Luma: Now, I've seen every argument in the book suggesting his credibility or lack thereof regarding the fact that he did not call Rosalina. The two most likely being the planned 'E3 reveals moved over to Nintendo Direct, his initial plan to announce her the following year, dated information (a faulty argument that I'll debunk later), or him simply not knowing the full roster yet. The third part does leave plenty of people sweating, but I'll get to part three later. Besides, with Rosalina's confirmation it at least gives likely or requested newcomers like Ridley, King K. Rool, and Mewtwo among other characters a fighting chance. For the time being, even without gematsu's confirmation, I'd barely call it strong evidence against her, so I won't bother trying to exploit her as the smoking gun.
Little Mac: Really, all one really needed before the E3 2013 trailer (where we saw the boxing ring for the first time) was the fact that Little Mac was one of the most hotly requested newcomers in the western world. Yes, I am familiar with the fact that Japanese fans in general didn't recognize nor care much about Little Mac's possible inclusion, but his popularity elsewhere as well as his history with Japan still stands. It might be fair to give him another point of credibility, however, by virtue of the fact that even with highly requested characters, there was no evidence whatsoever of his inclusion prior to E3 2013, and part one of the infamous leak was written beforehand (where he could have just as easily named other highly requested characters like King K. Rool or Ridley).
Greninja: Yes, he wasn't confirmed by name (which would be especially odd given he was revealed that very same day). And yes, I know he was simply put down as Pokémon from X & Y when Sakurai fleshed out his entire roster before settling for Greninja. And yes, I heard of the dated information tidbit as well. I'm still taking a point off since it'd make perfect sense to add a representative from the most recent Pokémon generation to the roster anyways, and the dated argument is incredibly faulty, as I'll reveal later when I cover the third part of the leak.
Mii Fighters: I can't tell if it was Sal Romano who referred them by the Mii Fighters or if it was the leaker that did it (all I know is that the same person also referred to Palutena as Goddess Palutena). I've always positioned Miis in the same vein as Wii Fit Trainer, only much more well known and more highly discussed and requested. And I predicted too that the Miis--if they were to be in the game--would be revealed at E3 2014 and at no other time before or afterwards. What ultimately got these guys in were due to the overabundance of [often asinine] requests of characters that Sakurai just couldn't realistically add (see Reggie for Smash), so this was his compromise. I'd be hesitant to give him a point for guessing a character that was just highly requested for (in one capacity or another) but otherwise dropped no hints of inclusion prior to E3 2013. However, the Mii [Fighters] and [Goddess] Palutena bits still bug me a bit, so I'll have to stay neutral for this one.
Palutena: The most obvious giveaway in regards to her inclusion had to have been the leaked Palutena images (which turned out to be well-done leaks that impressed Sakurai enough to exploit) back in January, and Sakurai's toying with so-called leak featuring and talking about Kid Icarus-related material. Really, anybody could have predicted that she'd be playable after that fiasco.
Pac-Man: In spite of Sakurai denying "special treatment" to Namco-Bandai in spite of them co-developing the game, was there really any doubt in anyone's mind that we'd get Pac-Man as a playable character? See Mega Man regarding mascots of third party developers.
And these are all the confirmed characters so far, and the score is tied 2 For and 2 Against this leak being fake. And no, no points for being 8 out of 11. I'll take a quick breather, and cover the rest of the gematsu leak and why I don't truly believe it to be a fake.