When making a redstone contraption with the new comparators, the game will freeze and crash every time with this set up. It seems not to happen with only 1 or 2 comparators, but after 3 or 4 it becomes constant. This bug has been recreated on multiple computers by multiple people.
Link to Screenshot: http://i.imgur.com/iJC0j.png?1
Step on the pressure plate, then once the torches turn off, get off the plate. Game will freeze within 10 seconds.