We change out our lights outside from time to time just to be different. My favorite for about 3 years runing was when we used purple in the trees and to trim the house and green in the bushes. (The last couple of years I've started to notice a few other people around town with purple lights.) My favorite for the tree has always been blue.
I detest white lights. We have so many people in our area that put up only white lights and I find it boring. This time of year it's kind of dark so I like the lights - they make things cheery - but I prefer color. All white, to me, just seems like more of the same lights you put outside for security and more of the same lights used indoors for general lighting.