What features differ between the Xbox 360 and PC versions of Minecraft?

According to the Minecraft Wiki, the Xbox version is closest to Beta 1.8.2. It is expected to be updated again.

Here are a few key differences between the versions. The full current list can be found here.

• Local 4 player split-screen multiplayer (requires HDTV, won't work on SD)
• Limited to 8 player online play (apparently cross platform multi, but not too sure about that)
• Newly designed crafting system
  • Seems to use a list for crafting, so you don't need to remember recipes
• World's limited to 862x862x128 blocks (PC is ∞X∞X256, expected to be increased in later versions)
• Cannot change difficulty mid-game
• Can't use mods, texture packs, or add player skins (8 skins included in game)
  • Texture packs and mods support is expected much later
• Includes tutorial mode
• Kinect support is expected to be added later

EDIT:

As of October 12th, 2012, the Xbox version was updated to include all features listed (here)

There are a few reviews of the new XBox version on YouTube. Here's one from CaptainSparklez:

It appears that the version used as the basis for the XBox version is pre-Adventure Update, so it doesn't have a lot of these newer features, like a food system, experience, sprinting, etc.

As far as XBox-specific features that have been added, here's a list of what I've seen so far:

• Nicely polished tutorials, particularly in-game ones.
• A new inventory/crafting UI that includes crafting recipes, so instead of a lot of trial and error to craft things it will tell you what you can make, what you need to make it, and how much of the ingredients you already have.
• Split screen play for up to 4 players.
• A world size limit, so there will be defined edges instead of an endless procedurally-generated map (which would take too much memory). It will still likely be huge, though.

According to the Minecraft wiki, it is running approximately PC version 1.3.1 http://minecraft.gamepedia.com/Xbox_360_Edition