This weblog is powered by MovableType, an almost free weblogging system.
Almost free means that you need to pay a small fee (US$ 150) if you use it commercially, which I do. So my excuse for not having done so yet is that they explicitly allow for usage as long as one is undecided about whether to stick with it.
From my experience so far, I must say that I'm absolutely impressed - it seems to be a great system. Kudos to the developers!