When it doesn't talk about its blogginess.
ProBlogger has a post about how some bloggers love having a blog -- and just can't shut up about it:
What worries me as I surf through many blogs each day is that there
seem to be quite a few bloggers (and some blog networks) who in my mind
are a little obsessed with reminding their readers that they are on a
Amen! If you ever see me talking up the fact that I have a "blog," and that my "blog" is great because it's a "blog," please find me and slap me. This is a place to post information about what's going on with online media and marketing -- and it's a place to discuss the various projects we're working on at Learfield InterActive. (Have I mentioned, lately, that we're starting to find our legs at the VisitColumbiaMo blog, after the first couple of weeks? I haven't? Oh, well, we are, I think. You chould check it out.)
The point is this: nobody gives a flying flip whether you're writing a blog or posting information to a website. They want to read the article they found via their Google search, or find the stuff you've promised them in their RSS feed. But they're not concerned with whether it comes to them via a blog or a newsletter or a website. Blogs make a lot of this possible -- but their blogginess is not what makes them valuable. Their content is. Their interactivity is. But not the fact that they're called "blogs."
Hat Tip: Amy Gahran