US 2004/5 -> 2006 color codes:
Exterior colors
Super White (color code 040) stays same
Black (color code 202) stays same
Seaside Pearl (color code 8S2) stays same
Driftwood Pearl (color code 4S2) stays same
Millenium Silver Metallic (color code 1C0) is replaced:
changes to Classic Silver Metallic (color code 1F7)
Tideland Pearl (color code 6S9) is gone, substituted with:
changes to the new color Silver Pine Mica (color code 6U0)
Salsa Red (color code 3Q3) is replaced:
changes to the new color Barcelona Red Metallic (color code 3R3)
+Add a new gray metallic exterior color, Magnetic Grey (color code 1G3)
As usual, the Japanese have different/additional color choices, so be sure to check the color code to be sure that it's the same one that the US will have. Japan has an additional off-white color, and a different blue color, but one less grey color.
http://toyota.jp/prius/exterior/bodycolor/index.html
I find it sad that I've been through
http://toyota.jp/ so much, that even though I cannot read Japanese I can easily find what I'm looking for... It's getting harder now that they're going so Flash/Shockwave-happy. (The download times are longer, too).