Project faithfully simulates Mario logic, next steps are tighter collision detection, projectiles such as fireballs, enemies, and breaking bricks. A lot of logic left to re-encode here.
But it's here to play with for now, will keep updating this page.
Check it out
Arrow keys move you around, Z/X are run/jump/spin/fire/etc.
I'll likely bang on this more at SOURCE Barcelona. It's the kind of thing I only work on at cons ;P.