I like the new avatar, Jiggy.
(Better than that one with Colette in the green outfit, which I actually didn't like so much.)
Anyway, let's see what we've got for possible updates...
The gap between Ness and Marth more or less showed that we're not getting all of the secret characters consecutively. So a secret fighter is (mostly) out of the question.
Stage? Doubtful. We just got Port Town.
There are no worthwhile Final Smashes left to deal with. However, I'm not ruling out Zamus' Final Smash entirely since it's not like we haven't gotten any non-secret material since the Japanese release. However, I still think it's unlikely since we also haven't gotten any updates relating to existing characters since Japan got the Game of the Forever.
I actually don't expect a Game Mode at this juncture. I think that the Game Mode video update more or less covered all of the bases in that respect. Here's where I part ways with Jiggy.
However, a music update is likely, and F-Zero hasn't received one yet. Combine that with the unveiling of Port Town and I think that we should be getting a song with that stage.
However, as Jiggy said, music updates are always paired with something. So what will it be paired with?
Hmmm...unfortunately, my gut is indicating a new normal item or Pokeball. However, my gut is incorrect more than it's right, at least when it comes to predicting Sakurai's moves.
However, given enough time, a thousand monkeys pounding at a thousand typewriters will eventually produce Shakespeare. Given that, my gut has to be right eventually.
So I'm going with music and an item update.