The main menu on certain computers. For mine for sure has it.
Has extremely severe CPU lag. It shows a pause, unpause kind of effect at a set intervel of 1 - 3 seconds and unfreezes 1 second after it freezes..
It effects not just the game but the Entire computer. Only when in the main menu. This bug might not be able to be fixed however.

A new option to be able to be toggle would help a lot for some people.
An option to disable the panorama view on main menu screen will help greatly. Bug can't be pinned pointed from my end on what does it. But it occurs no matter what when in main menu when you first launch game.

UPDATE:
In latest snapshot 13w41b

This issue spread to the ingame menu's also. The game is slowly becoming unplayable.