MOApp Software Manufactory (http://www.myownapp.com/) has launched myWPEdit, a WordPress client for OS X. It’s available on the MOApp website and the Mac App Store.
You can write with the software the same way you are used from Pages. Insert images by drag and drop and format text bold, italic or insert lists, blockquotes, etc.
myWPEdit supports HTML. You can use Markdown, multiple accounts, sophisticated templates for recurring articles and autocompletion for tags and categories and you can import already pre-written articles directly from other apps like myTexts pro.
myWPEdit can be tested without any restrictions for an unlimited time. Registration is US$9.99.