The TAG feature seems pointless. I’m not sure why it matters if I add a TAG or not. I guess it might be helpful if you browse through a lot of blogs and want to find ones that are most relevant to you.
The problem is I probably don’t use blogs enough for this to be helpful. I’m great at tagging things on Facebook, but I just don’t see the utility of doing it here. For someone who doesn’t use a blog regularly (unless it’s mandated for class) it just does not seem worth the hassle.