Bugs in Minecraft 1.3
Minecraft 1.3 introduces some long-standing multi-player bugs into the single player game. This is what to expect:
Sometimes the game will render far-away scenery before closer scenery, giving you a sneak peek underground.
If this gets out of hand, you can fix the problem for a while by going into the Options menu and toggling the Advanced OpenGL settings.
Sometimes mobs, such as villagers, will fall through the floor. It looks ridiculous.
Sometimes it will look like your livestock has escaped by passing through fences: however, they will usually ping back to where they belong as if attached to a bungee cord.
Sometimes areas are not properly lit the first time you see them: this is especially common on steep cliffs and village churches. Plant a torch in the dark area to force the game to econsider the lighting situation.
When slabs are placed in the top half of a blug, there are often horrible shadows underneath.
All of these issues are on the "to do list" for future updates!