I freak out when a new color of a gadget gets here, because it's just totally fun to see a familiar object rendered in a cool new hue — like the metallic silver option for the Nintendo DS [1] that you can now get in the US!
I like having the option of getting to pick the color when I'm make the purchase later. I take it so seriously, like the one time I had a car and got to choose what color would be driving me around. It's an extension of your accessories and the gadget itself (it's no doubt why custom Colorware [2] is popular).

On the other hand, there's a conservative part of me that likes basic-colored gadgets, that I can then use cases to temporarily change the color of the exterior. I'm a fashion lover, after all, so I like the variety and to be able to change it up with my outfits! For example, if the iPhone came out in red [3], I'd pass, choosing instead to sheath mine in pretty colored sleeves and cases.
But what about you — do you like getting a gadget in a different color, or do you like just changing its case for your color fix?