Is classic mode finally returning? I would say no. The two modes shown in the E3 demo are simply Bowser Party and the normal MP9 gameplay. The Treehouse demo shows off Bowser Party, along with the playable attractions in the Mario Party mode. Players collect Mini Stars again, and they are all together. The image of the board map also shows Mini Stars and Mini Ztars. The board itself is made to work with the car in mind. The game still has time before it comes out in 2015, but I wouldn't be hopeful.
E3 2014: Mario Party 10 - Treehouse Live Board #1 Gameplay Footage
E3 2014: Mario Party 10 - Treehouse Live Board #1 Gameplay Footage