Is a blog a narrative?

Ok, well I know that this is one of those questions that begs yet more questions just to begin with. What do I mean by blog? What do I mean by narrative? Both those terms seem to cover a multitude of possiblities. However, when I first came across the term blog, I assumed it was roughly synonymous with online diary, and so some kind of narrative. I guess the fact that Jill Walker as written a definition of this for the Routledge Encyclopedia of Narrative Theory reinforces the fact that it is seen as a narrative subgenre, and I'm writing a chapter on blogs for the new edited collection I'm working on (New Narratives: Theory and Practice). But when I started looking at blogs, even personal blogs, they didn't really seem that narrative-like to me at all. I went on a course about blogging yesterday, and the tutor, Paul Bradshaw, described his blogs as kinds of scrap books. So I guess I'm beginning to ask questions about how far narrative theory can help us understand the various sub-sub-genres blogs are creating, and how in turn blogging might start to redefine narrative concepts.