Here's a great mod from Sabach, just wanted to share it with you guys incase you haven't already heard about it.
http://forums.x-plane.org/index.php?showtopic=66227
This is a great mod that will enhance the sky colors and fix the terrible default looking clouds in X-Plane 10. It's an ongoing development so things will get better as the project moves on. But so far this looks much better than the original.