Had the indepth look at Wordpress as I threatened to do the other day. One of the first things I learnt is that wordpress is actually a fork of b2evolution. I had read that b2evolution was a good product but did not get to study it because of the problem with it's authentication systems.
Looking into other issues; it's refreshing to note that the templating system of Wordpress is pure PHP. Smarty and other lame templating engines are no where to be found. They call these templates themse and there are some themes available for download on the wordpress site. What's suprising is that they are so few in number.
The admin console of this blogger is superior to any other that I have seen and that includes movable type. Wordpress also appears to have a decent comment spam filtering system. Feeds, pings trackbacks, you name it wordpress has it.
What wordpress doesn't have is the ability to export blog entries into static html. Opinion is devided into the usefullness of this but consider this: the only difference in the URL for different posts is in the query string. That means your posts are not going to get rank very high by google.
You will point out that it's easy to overcome this with URL Rewrites. If you don't mind having a 43 line .htaccess file that certainly is a possibilty. Don't forget that having lenghty .htaccess files would mean an extra load on the server. Add to that the CPU cycles eaten up by the PHP engine to spit out HTML that could easily have been static.