(Mine are usually bitten, sporting tell-tale rinds of garden soil.)
From today's NY Times Style section:
Now there is another stylistic tic that would have been unthinkable on a proper lady in your Aunt Beatrice’s day. Over the last few years — since the era of the skull print scarf, let’s say, or the (metaphorical) rise of the Olsen twins — having streaked, chipped or just plain grotty nail polish no longer suggests drug addiction, manual labor or pure laziness. Like untied high-tops, thread-worn jeans and bedhead, it’s now part of a deliberate look.
But then I read further--it takes a lot of work to get the right "I'm so busy and important I don't have time to dart out to the mani for a touch-up today." AND-- you have to have that $5k handbag.