You've got to look like you're enjoying yourself when you wear bright colors. If you're confident and the colors genuinely reflect your state of mind, go make it happen, and F all the gray urban camouflage guys.
That being said, please don't be a fruit cocktail. There are many bad two-color clashes, and three colors is really difficult to get right. And don't wear them when you're feeling mopey and depressed. You look like a sad clown, and sad clowns make the baby Jesus cry.
