If you’re using desktop blogging client to publish your content, and you’re using latest WordPress version (2.5.1), you should have no problems at all. But, if you upgrade to WordPress 2.6, you should adjust some settings. I tried to publish using a regular method (setting up a blog, pointing to XML-RPC gateway, inserting username and password) for WordPress 2.6-beta3, and I got something not working properly.
The problem occurs because we need to enable the Remote Publishing settings first. For WordPress 2.6, go to Settings | Writing, and choose the appropriate settings. Without having these settings enabled, we are not able to publish entries using remote publishing method.