Wait that's a bad thing?
It's a full super Mario Bros game, going by the title the DS was 5 so this is Super Mario Bros 6.
The conference was stupid as they said nothing and highlighted the up to four players. I was going to write it off but did research and found info and more clips. It's actually mostly your usual 1P game, it has 80 stages over multiple worlds, and it plays more like a mix of Super Mario Bros 3 and 4(World) unlike the DS game which handled like SMB1 with SM64 bits tossed in.
This game will be worth $50 just as SMB3 was worth $50 in 1990.