According to the Clay Factory's Blog, several colors will no longer be available in Premo! Sculpey's 1-lb size:
Glow in the Dark - Zinc Yellow - Fluorescent Yellow - Alizarin Crimson - Fluorescent Red - Fluorescent Pink - Fuchsia - Copper - Red Pearl - Blue Pearl - Sea Green - Orange - Fluorescent Green - Green Pearl - Turquoise - Violet - Raw Sienna
The colors aren't being discontinued -- they just won't be available in this size anymore. But if you regularly buy any of these colors in this size, you may want to stock up now.