I have had the pleasure and sometimes displeasure of working with both Wordpress (this blog), and Movable Type (http://www.straightupsearch.com). Both are very good platforms, but for the price, I’m going with Wordpress. Movable Type is nearly $1000 dollars for a 20 author license. $300 for a basic license. Wordpress is free for everybody, all the time.
Movable Type is done completely in perl, and has it’s own proprietary templating codes which allows you a lot of flexibility when building custom templates. With Wordpress, you are working in a standard php environment. Wordpress is updated frequently and has seemingly endless resources available for adding style and function to your blog.

MT has it’s up’s and downs, but the cost vs the competition blows it out of the water.