I am glad to discover that on WP 3.0 WordPress and WordPress MU have merged. For all those running WP and holding off on using MU this are some cool news.
Also some new plugins open new doors to flexibility and adaptable code. HookPress is a plugin that offers webhooks, these can be used to develop Push notifications (very popular now due to some mobile devices) and more. It is still in a development phase but I believe it can lead to many more automated publishing schema.