Well, I use Textpattern (TXP) to drive my web design site (http://www.webjones.org) and WP for my blog site (http://www.babygotblog.com).
TXP does have a slick user interface but its templating system takes some getting used to, although once the lightbulb goes off in your head, you'll find it to be very powerful, very customizable. The same can be said, of course, of WP. Also, I understand that there's a brand spanking new release of TXP that handles comment customization a bit better. If you are going to experiment with it, be sure you grab the latest distribution files.
I find the current plugins offered for WP to be more varied; TXP doesn't seem to have as many. Both user communities seem very helpful so if you run into trouble with either platform, help is but a mouseclick away, usually. This can be important when navigating uncertain waters with a new program.
I cannot recommend one program over the other, as I use them both. But each does what I want it to do. I chose TXP over WP for my web design site because I liked the way it handled images and how it organizes content.
Of course, I installed TXP on my web design site waaay before WP 1.5 and its Pages feature were on the scene. And to be honest, I am seriously thinking of overhauling my web design site and using WP there.
You can post this exact same question in the TXP forums and see what you get. If you don't want to fiddle around with installing and playing with both programs, check out the OpenSourceCMS web site where you can read about, and even try demo versons, of pretty much all the CMSs and blog tools out there: