Link was shown to have a zair, I don't remember which trailer it was, likely a character reveal.
Nevermind, I found it. Yeah, zairs haven't been shown yet.
Oh, alright. I believe you, it's just that, that's where I noticed a possible dash dance the most so I was just assuming. xP
Samus still has her same grab (can be seen at 5:30 in the newest direct). We don't know if it can still be used in the air and whether it tethers or not, but assuming they don't as fact is wrong. That list won't be taken seriously like that.
Smoke = Hitstun visualization is a very nice theory. I've been trying to disprove it watching the direct very closely and until now I've been unable to.
Things I've noticed:
1. There's definitely longer
and shorter smoke trails - Sometimes when launched a character might only have 2 puffs of smoke while other times the same character might have 4
2. There's definitely longer and shorter durations - sometimes the smoke vanishes instantly, sometime it lasts 1-2 seconds.
I haven't been able to tell if a character can't act out of it because they are just so short in duration but character's can definitely act out of it almost immediately after it ends (which leads to believe the theory might be right).
Edit: For those who don't believe the game is much faster than Brawl and even has faster attack animations than Melee should watch Samus play. At 5:30 she does her grab and almost immediately acts out of it (even though she misses it!!!). Or watch Bowser Up-Smash or F-Smash and almost instantly jump to chase his target instead of having to wait for his body to come back down and settle (like in previous games).
Attack animations aren't the end-all be all of a game's speed (physics and momentum are a huge part too), but if they weren't a huge factor then L-Cancel wouldn't be important.
(And let's not get started on how fast rolls seem to have become).
Edit 2: Lucarios Up-B now seems to have 0 landing lag and at 21:00 he is able to follow up his own attack with an Up-B into a down tilt (he doesn't even walk, he just chases with Up-B). Or, it could just be that his Up-B now ends in a sliding kick which looks like his down-tilt.