I bought Skyrim last night and ran into a few issues that made the game unplayable for me.
First off I never installed the game. I was playing off of the disc.

Issues:
1) All text, except for in the loading screens, was completely unreadable. The button prompts resembled runes with squiggly lines inside of them.
2) All of the player models sparkled. The edges, including detail lines of the faces sparkled.
3) Tree/ terrain textures appeared to never load in properly. They appeared as flat green panels, with no texture detail.
4) Texture popping all of the place. First instance, the moss on one of the towers during the intro sequence, while you are still riding on the cart.

5) Continuously seeing character models sliding around when they should be walking. The first town that you come to, the character that you are supposed to be following ends up sliding up the stairs and through a door. The door opens, after he has already clipped through it.