Mojang has been quietly tweaking Minecraft's combat for a while now. Unless you are a power user of the game's forums or reddit, you probably don't even know it's happening. The latest version, version 6, can now be installed manually for the Java version (check this thread), and is mostly a series of corrections to the previous version's testing.

For example: 6 months ago, Mojang tested "coyote time" in combat. This was basically a small auto-aim, intended to make combat with small enemies like bats and rabbits less frustrating. However, this implementation proved to be unpopular, especially with PvP-focused players, so it was removed completely in the testing of the new version.

Smaller creatures now have a slightly larger than normal "bounding box" instead of "coyote time."

Many other changes, mostly status changes: spontaneous recovery is now 1 second faster, and meals are interrupted when attacked.

Here are the full changes via reddit:

Aim assist:

Shield changes:

Axe changes:

Bow/shot changes:

Food and hunger changes:

Other changes: