So as I figure out what kind of blog I want, I'm going to poke around and look at what other people are doing.
Here's one approach to this whole reporter-blog thing: posting notes as you work on a story. That's a blog post at the Center for Environmental Journalism. Some dude is working on a story about climate change and here he writes about an interview with a scientist. It's moderately interesting and well-written. I don't see anything that makes me want to follow it and read more, though. There's no shortage of places to read about global warming.
Olivia Judson blogs on the New York Times website about evolution. She has a nice writing style, but I get really impatient waiting for her to get to a dang point. I don't love her writing enough to keep going. Maybe in a book, but really, I have a short attention span online. (I admit, I didn't read the above post all the way through, either.) I'd be happy if she posted shorter pieces more than once a week, rather than 1,800 words weekly. Other people appear to be fans - she gets tons of comments.
So, the conclusion thus far: I apparently can't pay attention for long enough to give an intelligent critique of these blogs. Lesson: Short is good.