I've been away from academia since I dropped out of philosophy grad school in 1997, so I'm out of touch with recent developments in philosophy. What are the most significant philosophical books or papers of the past eight or so years? (My main areas of interest in grad school were metaphysics and philosophy of language, but I'd be interested in your answer whatever your specialty.)

If I could look back slightly farther than you asked to the last decade in philosophy of mind, I think one of the most important books published was David Chalmers' The Conscious Mind (1996). This book brought consciousness back to the forefront of discussion. One important trend in philosophy of mind in the last decade has been the advent of representationalism -- the view that consciousness (or what we might call phenomenal character) ultimately reduces to representational content. Important books on representationalism and related issues include Michael Tye's Ten Problems of Consciousness (1995), Fred Dretske's Naturalizing the Mind (1995), and Charles Siewert's The Significance of Consciousness (1998), though there are many others.

Are women philosophers more insightful than their male counterparts?

I don't think that there's any special reason to think that female philosophers are more insightful than male philosophers -- or vice versa, for that matter. Nonetheless, it may be true that female philosophers on occasion have different insights from their male counterparts. For example, feminist critiques of traditional ethical theories (like those offered by Kant and Mill) suggest that those theories focus on masculine values and ignore values that are of fundamental importance to women. Feminist philosophers have worked to develop an "ethics of care" that looks at moral questions very differently from traditional theories.