There are some really nice programs to help you blog on OSX. One of the nicer ones is ecto, but having used emacs to blog, it would be nice to use something similar (but better). Textmate has two blogging plugins: the build-in blogging bundle and blogmate. Let’s compare them.
Blogmate is a bit easier on the eyes, it has (kind of) the same panel as ecto, which makes it easy to see what posts you have made so far. To write a new post, you just start typing and when you are done, press ‘Send Post’.
All of this is possible as well using the regular blogging-bundle. The plus of blogmate is the window with a list of your posts, the plus of the blogging-bundle is better headers when you download a post to edit. When I started with blogmate, and then wanted to edit the post with the blogging-bundle, the bundle got mixed up, and thought my blog was written in markup, while on wordpress.com you only can use html using xmlrpc, as far as I can tell.
Opinion: Both are nice plugins for textmate, and I will probably use blogmate for the nice list, and use the regular bundle for editing.