My unpopular opinions:
1) **** WFT, she's a *****. (lol)
2) Impa makes much more sense at this point than Sheik. I wish we would've got her instead.
3) Chrom makes white bread look exciting.
4) I really am not a fan of this recent or this casual bent Sakurai is on. Wii Fit doesn't need it's own character, it could've been represented fine under the Mii umbrella. Chrom may be recent, but he's super boring and bland and I'd rather have almost any other Lord playable instead. Greninja looks like a fun character... but it's clear he got included because he's sixth gen, and I wish that didn't play as much of a priority as it did.
5) Nintendo is being dumb releasing the 3DS version first. Even if it's further in development, Nintendo does not need any more reasons for people to dote upon the 3DS at the cost of the Wii U.
6) Rosalina is too big. Little Mac is too small.
7) Ridley is not too big, but Sakurai probably sees him as less than feasible.
8) I do not like the idea of characters from traditional fighters in Smash, with the sole exception of Sukapon.
9) Snake had no real business being in a game celebrating Nintendo, certainly not over some other Konami characters, but he was still a cool character. I hope he returns.
10) I'm still torn on whether I would've rather had Sakurai make a SF game or Uprising. (Not really Smash related)
11) People who blame Krystal for the demise of SF are dumb, people who think she would be added without the staff are also dumb (This one might not be an unpopular opinion)
12) Jigglypuff taking up a spot on the roster kinda sucks. Nothing against the character, but if she was never included no one would still care about her.
13) Sakurai aiming to include 25 newcomers in Brawl (at one point or the other) but not decloning Ganondorf is ridiculous (that's probably not unpopular either)
14) I like the idea of Chorus Men, but only if there are three of them
15) I think the pedigree of Smash only improves with third-party characters, assuming they are used in limitation and with relatively strict standards
16) When Nintendog shows up my immediate reaction is "Dawww", not annoyance
17) I was upset Pokemon Trainer was not referred to as Red. I suppose that's a fairly moot point now.
18) I would've rather had Bulbasaur, Wartortle, and Charizard than what we got
19) That damn WFT.
20) I've never disliked the idea of getting Duck Hunt Dog, I think he'd be a funny, original character who fits the iconic Nintendo character mold perfectly
21) I think including Nintendouji would be a better surprise character than any we've got previously, as he can represent Nintendo's hanafuda history
22) Having two boxing rings takes away from the Punch-Out version
23) I'm quite happy characters no longer transform. I never liked that mechanic.
24) I wish ZSS's boobs were smaller, they look silly, but the rest of the character looks so great all in all I don't really care
25) Mii is a perfectly deserving character, and as much as I don't want them, I don't see any sound arguments against their inclusion.
26) The Sal leak is totally real, either that or he's a wizard.
27) If there isn't voice chat, I won't be too bummed.
28) Dr. Mario to date has been the dumbest, least deserving, and laziest inclusion.
29) The Villager's recovery is ill-fitting to the character.
30) Tingle is without a doubt the most deserving Zelda character who isn't one of the main three - don't care if he's included though
31) Yoshi being held off until the Direct was dumb. Either have him in March or wait for his Japanese release.
32) I'll be upset if there aren't CG cutscenes in the game past the newcomer trailers
33) Zoroark should've been included over Greninja, but at least he's a pokeball
34) I'd love to see Geno in Smash
35) I'm happy we still have a Temple-like stage, even though NPC was an abomination
36) Even though I like Ness and Lucas, Mother didn't need a second character
37) People need to let the Melee comparisons go. It's not the be all and end all of everything, and I'm glad this game isn't just going to be a Melee 2.0
38) I fundamentally don't see what people see in Chrom.
39) Bah, WFT.
40) Sakurai needs to stop jerking around the Ridley supporters. I mean he's a troll and all, but just put them out of their misery.
41) I really hope stickers don't return
42) I do hope the Chronicle returns, I found it interesting. Perhaps a bit of a redesign to make it more exciting though.
43) I hope there's day one DLC, not on disc though.
44) Announcing SSB4 in 2011 was too early
45) I'm not terribly saddened by the probable fate of Squirtle and Ivysaur.
46) I'm still not sold on Smash Run, though it having actual existing enemies is a good start
47) It might sound contradictory, but Sakurai is both more open-minded and more close-minded than we give him credit for
48) I believe Sakurai is prioritizing the wrong factors when adding characters this time around
49) No single newcomer addition or omission will ruin this game.
50) **** WFT, she's a *****.
Phew.