Wordpress Importer does a basic import of a wordpress blog.
The main idea is that someone can take their old content and have it represented on a concrete5 site.

What it is doing:
  - Uses a wizard-like interface to import
  - Import is incremental -- keeps user in the loop and continues where it left off
  - Includes basic image import
  - Uses WP's own text formatting functions so everything comes through looking like a paragraph, etc
  - Pages and post import to different pages, and use different page types if selected
  - Page parent/child relations kept
  - Imports Wordpress Categories to the attribute 'wordpress_categories' - no nested categories, but the category name is kept
  - Imports Wordpress Tags to the 'tags' attribute
  - Removes all blocks from "Main" and "Blog Post More" areas on newly created pages to keep lipsum text from showing up
  - Imports comments and comment dates
  - If users exist with the same username as a post author's username, uses that user for the author of the newly created page

Not so great:
  - No "Start Over" on the first step.  Choosing a new database when you have existing records doesn't do anything so the dialog shouldn't be there.
  - Not selecting a page to import under is very bad. Hundreds of pages show up under "home" and the link does not work at the WORDPRESSED step.
    - Should not proceed if "Posts" are going under Home. This basically ruins a site.
  - icon.png does not look good

Would be nice:
  - Option to import just posts or just pages.
  - some kind of rudimentary support for image captions, like <div class="wp-import-image"> <img /> <span class="wp-import-caption">caption</span></div>
  - Somehow keep post url structure, or update internal links in post content
  - Better import of images, script as is tries to import flickr images that probably shouldn't be imported
  - Keeping pingback comments would be nice if there was a comment block that supported pingbacks