There are also colors that kind of put people off... the Keeper cup with its brown color reminds me unpleasantly of a plunger! GreenCups also seem sort of weird to me, because it seems like it would stain unpleasantly.
Anyway, I thought it would be interesting to see what colors people really like, and which ones they dislike. Or there any colors you want but can't get?
Oh, and carry bag colors can be brought into this too! :)