I'm happy to report that zombies in update 0.3A have become much better, thanks to the reworking of their behavior they are now: 
- Don't get stuck in the player
- Not able to push the player into the wall

Leaderboards are now available in-game!

There are currently three tables available:By number of zombies killedBy number of players killedBy number of bottles of beer drunk

Also 

You can open the Leaderboards menu by pressing the “L” button
Or in main menu