Poster is an iPad only application for WordPress publishing. It's the best blogging app for iOS… period. And I've tried them all.

It was just updated to 1.2 which adds support for uploading images, custom slug settings, and introduces a monospaced font for the editor. Of course, the big sell (for me, at least) is markdown support. It converts your markdown to HTML when you publish a post. The same great features of supporting custom fields, etc, are also there.

This app far surpasses the official WordPress offering. It's not even close.

If you use WordPress, get this app now.