I'm kinda a science-junkie, so I scan several science-related sites and blogs every week. I've come across a few that I like and I thought I'd share them here. These are probably enjoyable by a wider audience than some of the more hardcore ones I've got bookmarked.
80beats is a science blog by Discover Magazine. I like its posts because they usually have snipets from source material/sites along with links right to those sources. Let's see the WSJ or LA Times do that.
Observations is a science/nature blog by Scientific American. They cover a wide variety of subjects, and hide any of their own bias pretty well.
Both of these blogs are also relatively kind about not including too much annoying animated ads. Although I've started using ClickToFlash to block flash content in Safari. I recommend that also. It's basically a Safari version of FlashBlock for Firefox.