Originally I thought we were going to get a enhanced port, with like... two to four new characters and some amalgamated content from both versions. I didn't think there would be a massive upgrade or anything, in part because I expected the game a little sooner than we'll be getting it. Then it just kept on not showing up. And the last round of Smash amiibos launched at a super random time, which, while could be due to licensing issues as posited, I believe is more indicative of the game getting pushed back past its initial intended release.
Now I believe we'll get something tantamount to a step between MK8D and Splatoon 2. I've always maintained Smash 4 will be the base, like Splatoon 1 was clearly the base to Splatoon 2, but I do think we'll get enough new content to the point where Nintendo, if they were inclined, could brand the game as something different than another version of Smash 4. Don't get me wrong, I think the game will clearly look like a Smash 4 enhancement, it will just have enough to overly differentiate itself. Whether this is an increased amount of characters (my new guess is up to eight) and stages, a new mode, or an overhauled UI, I do think this game will turn out more like a Smash 4.5 than a Smash 4 Deluxe.
This is, of course, just my shot in the dark. But we'll see.
I don't believe we're close to a real Smash 5, regardless of how Nintendo brands this game.