Would you care if someone else wore a white dress to your wedding?

There's that rule that says only the bride should wear white because otherwise it is seen as upstaging the bride. If I had a wedding, especially an outdoor wedding, I think it would look nice to see my guests wearing white and other light colors. It would add to the fairytale. How do you feel about this rule of etiquette? Would you feel like you were being upstaged or do you not really care?