... unfortunately no two bloggerApi / metaWeblog API implementations seem to work the same way, or even use the same message structs, but you already know this, I'm not the first (and won't be the last) to rant about that. I live in hope that the rounds of discussions of a soap based blogging API result in something more concretely defined.
Followed a couple of days later by a piece on Slightly Uniform Interfaces:
There's a lot of power in uniform interfaces, for one, it means I can write a single tool that should work with any server that implements that uniform interface. In reality, it seems that the various XML-RPC based blogging API's are slightly uniform interfaces, all the implementations are kind of the same, but different, for example, Moveable Type doesn't implement metaWeblog.getCategories, Radio's implementation of blogger.getUsersBlogs doesn't return a blogname value in the response. In metaweblog.getRecentPosts, Radio and MoveableType return different types for the userid value. I have an even greater respect now for the number of different webloging tools that NetNewsWire supports.
Finally, he decides the RESTLog API is a better alternative:
I've switched the blog over to a RESTLog API style implementation I whipped up in. NET, I could battle the metaWeblogApi no longer.