No, in fact you can autopost to a self-hosted Wordpress installation. I'm doing that on one of my sites. First make sure that the following setting is checked

No, in fact you can autopost to a self-hosted Wordpress installation. I'm doing that on one of my sites. First make sure that the following setting is checked in your Wordpress control panel Settings>Writing: Enable the WordPress, Movable Type, MetaWeblog and Blogger XML-RPC publishing protocols. Then you go into the Posterous settings for autoposting, provide the url of your wordpress site, admin username and password and that's it.