Traditionally, white or creme for the bride and black or white for the groom. I have seen red, black, and purple wedding dresses. So, any color that you want.
I believe every color is OK for YOUR wedding day, however popular superstitions tend to forbid certain colors; like yellow (color of unfaithfulness) or black (mourning).
Most brides will wear a white or an eggshell colored dress. But also traditionally you want to wear something old, new, borrowed and blue (suggested as accessories) for good luck.