In WordPress right now, a post is a post (which is different from a page). Version 3.0 allows the creation of custom post types. For example, if I want to use a WordPress blog to manage a course I’m teaching, I might have Lessons, Quizzes, and so on. In V3, I could create Lesson as a custom post type.
An excellent account of custom post types is provided by Konstantin Kovshenin. He makes the point that custom post types are about organization, rather than about functionality. I could, using WordPress 2.x, post lessons to a course blog, but I can organize things rather more neatly using the custom post types.
I have indeed added the custom post type Lesson to one of my test sites. I then added a lesson, and a regular post about what I had to do and some things that came up along the custom post road.
Most bloggers will never create a custom post type. The feature is interesting for the Thing Management Systems that can be built with it. For example, my lesson post type might be a step toward a Course Management System built on WordPress.
To get at custom post types from the dashboard, you have to install a plugin, and to really work with custom post types, you have to edit the WordPress PHP code. I’m not sure what plans are in place to make the feature more easily accessible.
Neither am I sure how custom post types will show up in WordPress.com. My guess is that, if the feature shows up at all this year, it will be in the form of a few new post types (video, etc.), rather than as a dashboard option to add and manage new post types.
If you have better information, or any kind of different perspective on this, feel free to share in the comments. Next up in this series of posts on WordPress 3.0 will be something I’m sure will be in WordPress.com soon: the new default theme.