Team dark. Purplish shades work best, as they make my light greeny-grey eyes look greener. For some reason light-coloured lipsticks just make me look washed out. Maybe it's because I have neither high- nor low-contrast colouring (white skin with light to medium brown hair), and increasing the contrast seems to improve things.
Also, I have the opposite approach to make-up as Sarah the White: I wear only mascara on my eyelashes, and no other eye makeup. Eye makeup tends to make my deep-set eyes look even deeper set, which I don't like. So a bolder, darker lip colour seems a better option. My smile is big and my teeth are white, so why not play that up, rather than trying to improve my eyes.