TechCrunch wonders what the definition of a blog is. They question whether "blogs" that don't allow comments, like the Office Google blog, are really blogs:
The current definitions of “blog” in most dictionaries don’t mention reader comments at all when defining the term. Wikipedia says only that “the ability for readers to leave comments in an interactive format is an important part of many blogs.” According to these sources, the minimum requirement for a web site to be a blog is that it have content, and that it be sorted in reverse chronological order.
I believe the term “blog” means more than an online journal. I believe a blog is a conversation. People go to blogs to read AND write, not just consume. We’ve allowed comments here on TechCrunch since it started. At times, user comments can be painful to deal with. But they also keep the writer honest, and make the content vastly more interesting.
Should the definitions of “blog” be revised to exclude journals that do not allow reader comments? Yeah, absolutely. And Google may think so, too. At the end of their post, they write “And before long, perhaps you can begin leaving comments directly. We’re working on that.”
For some people the definition of a blog is pretty wide. I've heard people refer to Slashdot as a blog, and some people call this site a blog. I prefer to call DV Hardware a news site.