SETT supports importing all blog posts and static pages from WordPress. First you need to export all of the data from your WordPress installation as an XML. Instructions are here. Make sure to check "All Content".
To get to the importer, click the "Upload your XML Here" link at the bottom of your Blog Settings page. There you can upload your XML.
On the next screen, you'll have the option of remapping all of your images. If your images are hosted somewhere besides your domain, or if you don't have images in your blog, you can skip this section.
The WordPress importer is a work in progress. It works well for basic WordPress installations, but sometimes plugins muck up the database and present a problem we haven't dealt with before. If that happens, SETT will automatically email us your XML and create a ticket for us to figure out the problem and fix it.
Of course, you can always contact us at firstname.lastname@example.org and we'll help you out.