After hours of deliberation and research on this topic (procrastination ftw), my conclusion is: real.
1) The massive amount of energy expended from Reddit, SmashBoards, GameFaqs, and beyond has yet to find comps for these renders, and they're seamless with the rest of the characters.
2) Multiple leakers from various websites and timeframes leaking the same data.
3) Corroborating screens from Famitsu (for the Tomodachi level) and GameSpot (for the color swap on Fox's background image), along with new angles on the level--too hard for so many coincidences to happen at once.
4) Pixel discrepancy on character select matches pixel discrepancies in the E3 demo. It would be hard for a currency counterfeiter with a lot more to gain to be able to surmise that level of detail, let alone go through the effort to recreate it.
5) Sakurai has foreshadowed some of the new characters in this leak, which is a trend that matches already-announced characters and stages (Kid Icarus image dump by Sakurai after Palutena image leak plus Palutena trophy tease, empty Mii cage in the Find Mii stage, Rainbow Road in the Rosalina/Luma trailer). It stands to reason that Game and Watch was a tease in the Pacman Trailer along with Shulk teased by composer reveal and Xenoblade devs retweeting Sakurai, Dark Pit teased in Palutena reveal, and maybe there's more to come (Ridley shadow from earlier Smash video--don't remember which--could be evidence backing up Ridley DLC, but I doubt it)
6) Ice Climber cut or moved to DLC makes sense given 3DS and Sakurai hinted at it.
7) Bowser and DeDeDe, while out of place technically, seem to be lumped into their own weight class, which lends their spot on the roster a (tenuous) rationality.
8) This is mostly speculative on my part, but I've been unduly hyped for Smash games since 1999 and thus combed for every shred of data. Just from my sheer volume of reading over the years: the Duck Hunt Dog has come up an absurd amount of times and fits all of Sakurai's criteria for uniqueness, as well as the tradition of throwing in an off the wall retro favorite.
If I were on a jury for this case, I'd vote real in a heartbeat because the circumstantial evidence is just too compelling.
I also believe that there's some good evidence for Chrom: he might have been a tease in the Robin reveal. No reason why he couldn't hit as DLC, and it would make the Gematsu leak complete. I tend to believe the leaker when he says the Chorus Men are DLC--the Rhythm Heaven enemies in Smash Run were likely a tease, and they probably have a team aspect to them, which makes them harder to work into the retail release ala Ice Climbers. This evidence is less compelling than other things related to this leak, but noteworthy nevertheless.
Real. Will be astounded if I'm wrong, but it's been known to happen. Duck Hunt Dog is for sure on my new main rotation.
