Blog Qualities

Just a quick note, I'll get back to this later. I was reading "On the bursty evolution of Blogspace" (Kumar, Raghaven, Novak, Tomkins) and pondering what the defining qualities of a blog are. So a very brief starter for ten is:

• it's closely linked to time - date stamping, date ordering
• usually to a single person - which ties it in closely to trust and reputation
• highly linked (whether cross-blog postings, blogrolls or intra-blog linking in terms of Comments etc.) - this then means (along with point 2) that they form a tight sense of community

Anyone else have any particular "defining" thoughts...