I haven't tried WordPress out so much, but I've been using Textpattern for well over a year now, and I'll never switch (unless I build my own some day). The tag-language is wonderful and pretty much logical when you want to learn it. The community and the developers are nice and you don't have to fight your way in to it to get help or to make a request or plugin. , the plugins are just wonderful. There's plugins for the biggest issues that Textpattern doesn't handle, and when new ones show up, there's new plugins. Many of the early plugins have turned in to features in Textpattern.
best of luck!