Why don't I blog more?

I have a Blogger account, but I don't use it much.
I have a Twitter account, but I don't use it much.
I have a Facebook account, and I use it more that both previous.
Why?

Twitter's concept, "What are you doing right now?", seems interesting, but has never quite grabbed me as being something I want to use to commit my activity to permanent record.  It seems a bit too trivial.  What are you doing right now?  Well, to be honest, right now I'm writing a Tweet.  Or, to be less literal, I'm sitting around doing not much.  Or walking, or driving, or whatever.  Not earth-shaking stuff.

Facebook's concept, "What's on your mind?", has always seemed more relevant to me.  It's as if I'm sharing something with a friend in the room.  Facebook is a happy medium between fluff (Twitter) and weighty (Blogger).  But I think the big plus is the fact that there are so many people on Facebook.  There's a critical mass of people I know in the same virtual community.  So there's always something new to see, and when I post there's always someone out there who sees it.

Blogging seems to me to convey a higher threshold of content.  By that I mean that blogs are used to record thought-out writings.  More like essays.  If Twitter is a clause, then Facebook is a sentance.  But Blogger is an essay.  And often I just don't feel like having to write an essay.  I just want to write a few sentances.

I guess Facebook has found the right balance for me in communication.  I'm not much of a texter.  That's mostly because I don't have a smart phone.  But also I'm not in the habit of communicating in small bursts.  So maybe I would equate Twitter with texting, or IM.  Then Facebook is more like email.  I use email all the time.  Since I'm familiar with email, Facebook is a more comfortable fit for me.  Then Blogger would be like.. all I can think of is writing an essay.  To me, it implies a more thought-out body of content.

Twitter:  unfiltered stream of words from my mouth.
Facebook:  coherent thoughts on a single subject.
Blogger:  developed thoughts with a bent toward persuasive essay.

And most of the time in my daily activity, Facebook is where I'm at mentally:  coherent thoughts on a single subject.