There is a small chance Diddy's pictures in the ring were taken before Little Mac's reveal? Maybe it was a slip. Guess we'll have to wait for more pics showing the ring.
While a possibility, it seems odd to me. Because one of Diddy's pics has Little Mac shown and the ring is WVBA themed.
I agree that only when more pictures of the stage are shown will we be able to draw a conclusion or at least make a plausible prediction. Of course, this will probably be definitely confirmed when we get our hands in the game or perhaps if Sakurai makes a statement about it in a a picture of the day.
Consider this way of thinking on why I think the boxing ring changes theme depending on Little Mac's presence on the stage:
- Let's assume the stage is one and the same.
- Okay, Little Mac is in the stage. Well, he's participating in a WVBA boxing tournament and the other characters are the challengers.
- Little Mac is not on the stage. The boxing ring is just hosting a regular Smash match, thus being generically themed.
Kind of like how real life stadiums and rings are often decorated differently depending on the event. If we apply the same logic to this stage, it's easy to understand why the stage changing depending on Little Mac's presence is a valid (and likely IMO) possibility. Not to mention you can make the assumption based on the pictures released so far.
Of course, I could be wrong.