The last time we heard about "Super Mario Bros. Crossover" version 3.0 was in the trailer above, which was released in April. But now, courtesy of a tip from Beed28, we now know that this version has finally been released. In addition to the inclusion of Easy and Hard modes, there are also tons of skins which homage all sorts of video games, including numerous Mega Man characters.
Additionally, developer Exploding Rabbit has offered an update on their "Super Retro Squad" project, which takes the gameplay concepts behind "Super Mario Bros. Crossover" and applies them to an original game. You can see that update below.