There is a delay with certain aspects of the game.

Redstone:
Instead of redstone being activated instantly there is a very noticeable delay. This also occurs with many other redstone related items.
1)Hoppers take a long time until they are able to pick up items
2)Buttons stay pushed for a long time as if they were stuck
3)Repeaters have a very long delay
4)Levers have a delay when outputting a signal
And this goes for other redstone related items

Mobs:
Mob movement has a very very noticeable delay. When hitting a mob it seems the take its normal course in the air but in slow motion. This delay also takes place in other mob movements.

Items:
1) When dropping an item it seems to stay in your hand a couple seconds after hitting the drop button.
2) Also after the item is dropped it has a very long delay before being able to obtain that item again

Potions:
1) Splash potions have a short delay of giving you the effect when thrown on the ground.
2) Splash potions also seem as if they go through the ground when thrown instead of breaking on impact.

All of these claims can be easily tested
Thank you for your time
Hope this helped the game