From what it shows near the end, this remake has been around for a while now. I'm sort of sad that after so much time the Mario model still looks so offputtingly shiny.
This. Assuming it ends up being a good quality remake, they should at least let it be released on the Wii U.
Nintendo have given the all clear for people to do stuff like this with their IP's. In fact, they've turned table and are outright encouraging it and offering incentives. Dunno whether it'll be free but I assume so since I can imagine Nintendo still taking issue with making money from their IP's.
Impossible. Nintendo would never let a random indie developer release a remake of their IP on console. SE wouldn't do it, Nintendo wont do it. Even if they don't issue a cease and desist, it's probably best nobody gets their hopes up.