Margaret Simons in her Towards a taxonomy of blogs says that before we criticise bloggers we need to define our terms. The word “blog” is now manifestly inadequate to allow us to talk in sensible ways about the many different things that are happening in internet based publication by individuals and groups. My understanding is that 'the blog' is just a media technology (similar to 'the book' or 'the television'), which is then used in any number of different ways. So we have specific forms of blogging---public opinion, for instance, is different from junk for code or philosophy.com
Simons says:

I am going to make an attempt to invent some new words for different kinds of blog, in the hope that readers will dive in, add and improve. Where possible, I have tried to adapt the terminology of the past, including that which accompanied the invention of the printing press. I think historical resonances can be helpful in illuminating what is going on in new media, as well as reminding us that this is not the first time that technological innovation has changed almost everything about how we communicate. Certain human needs persist. The means of satisfying them alters.

The Exhibition Blog. I could have called these blogs “vanity publishing”, but I don’t like the pejorative overtones. These are blogs maintained by writers, craftspeople, artists and artisans of many kinds in which they bring their creations to a wider audience, and sometimes discuss their methods and thought processes. Take, for example, the many blogs on quilting, such as AroundtheWorldIn20Quilts, which is a collaboration between quilters in the Netherlands, the United States, Britain and Australia. Sometimes Exhibition Blogs also serve as Diary Blogs