Although this may be heresy, i use the perl powered MovableType engine.
I like it because of the ease of setting up new blogs and new authors, in fact most of the admin stuff is very easy.
I dis-like it because i can't extend it, due to lack of interest in learning perl.
Perhaps not the flavour of the month like Wordpress, and not Open Source, but i've found it to be a capable commercial tool.
It can do static file output, or dyanmically served pages, via PHP. Internal storage comes with a variety of options. "Free for personal use" licence available. Good anti-spam tools. Open-ID plugin available. Threaded comments available via a hack (which is ugly).
Good luck with your choice!
Perl would be fine -- then I wouldn't even be tempted to modify it ;) -- but the proprietary part is a big turn-off.
Has anyone else noticed that there was all sorts of buzz about MT, and lots of blogs using it, until it changed its licensing? Now I almost never hear about it; zero buzz, and proportionally it seems like a fairly marginal piece of software. Well, really it's that the hosted options have become incredibly dominant; and even though MT was never open source, people in the open source community were suddenly reminded of that (and left in droves) when they changed their licensing, and those are the blogs I tend to read.# Ian Bicking