The big difference between a blog and a Pretty Pretty Princess Diary jammed under a mattress is that a blog invites a conversation. I pick the topic, write whatever I have to say about it, and then wait for YOU to respond in whatever way you see fit.
I like agreement. (Obviously.) I like disagreement. I like constructive criticism. Basically, if you're not an asshole, your comment will live happily-ever-after on my site. I moderate all comments, and if I feel your comment is attacking, mean-spirited or just plain creepy, I will remove it.
Also? I write back to you (if you made your e-mail address available) because I don't want you to feel like your lengthy comment just flies out into cyber space, unnoticed and scorned. I noticed it. I think it's special. I appreciate it.