John Tierney, a conservative/libertarian/who knows? columnist at the NY Times has started a science blog. I'm usually not very optimistic about pundits commenting on science - the results are rarely good, with one of the worst cases being Gregg Easterbrook. The pundits usually have a muddled grasp of the technical issues and view scientific debate through a deep partisan tint.
However, the NY Times science section has much higher standards than opinion magazines like Slate and The New Republic, and so far Tierney's blog looks interesting. I recommend checking it out.