Minecraft loads fine and allows me to successfully load a world.

If I save and quit the world and then open it again or another world the graphics fail to load properly displaying repeated patterns of blocks that are not there (the real blocks are there, but are not displayed). Moving the mouse around causes the displayed blocks to randomly change.

It's hard to be certain, but I believe the displayed blocks are always from a randomly chosen portion of my world, perhaps as much as a whole chunk, which is repeated as far as the eye can see in all directions.

This happens in 1.8.8 and all 1.9 snapshots.