So just a minor thing I noticed:
If you look at the character menu that is at the bottom of the official website, currently there are 4 full tabs (of 9 characters each) and then the 5th only has two characters.
Well, if you compare the website roster with the full roster revealed through the gameplay today and the CSS leak, there are 11 characters that have yet to be "officially" (by Sakurai himself/the website) revealed: namely, Ganondorf, G&W, Wario, Jigglypuff, DHD, ROB, Bowser Jr., Falco, Ness, Dr. Mario, and Dark Pit.
Why do I bring this up? Well in that menu, there are 9 slots per tab, and the unfinished tab has two spaces filled (by Bowser and Pit), and then 7 other slots to be filled.
So if we factor in these 11 characters that have yet to be added, we finish the 5th tab and then start a new one that will fill 4.
Now, let's make the assumption that Sakurai or whoever manages the formatting of the website would want each of these tabs to be uniform in size, as in, 9 slots per tab. If we make this assumption, then it would be logical to conclude that they wouldn't want to have a tab that has any empty slots.
Let's go back to the 11 characters that are still unaccounted for, as I said, if we add these to the menu, the unfinished one will fill and a new one will be opened that will have only 4 out of the 9 menu slots filled for that tab (once again this assumes that each tab has the same number of slots). Which means that there will still be 5 slots that are empty, implying 5 more characters still have yet to be introduced as a part of the roster.
I don't intend for us all to have false hope, as this is just a theory based on the idea that Sakurai's team would want uniform formatting for the character menu, obviously, but I found this information interesting.
Just something to think about...