b) I will check it twice or so per day. This is on my personal account. I will retweet or post to it a few times per day.

I like twitter, but I don't love it. I would use twitter often when third party clients were popping up.

I was using app.net for a while, but my friends never took to it. (this is within the first months of its launch) I paid for it, and liked it, but it lacked the network effect.