Paul Kedrosky on what he looks for in the blogs he reads:
I don’t want volume or comprehensiveness; I want surprise and interestingness. And to be even more clear, I don’t want surprise or interestingness in a Digg sense of the word, with naked nonagenarians or raccoons with their tongues stuck to metal poles, etc. I don’t want an information freak-show. I want things that I would have normally read, but wouldn’t have found, nor would have most people that I read. Something that changes the way I think.
I think that’s a pretty good description of what many people are after in their blog reading. It’s one of the big reasons that I love blogs that are outside my areas of professional expertise and outside of my usual interests. Reading about topics that I don’t already know a lot about is intellectually stimulating.