Stellar plugin!! A long time favorite.
I have several WordPress.com and WP.org blogs. With this plugin I can auto-post and update, from the original post on my sites.
WordPress Crosspost posts to your WordPress.com (or JetPack-enabled) blog of your choice whenever you hit the “Publish” (or “Save Draft”) button. It can import your reblogs and other posts on WordPress.com. It even downloads the media attachments in your WordPress.com posts and saves them in your self-hosted WordPress Media Library.
Transform your self-hosted WordPress website into a back-end for your WordPress.com-hosted website. Create original posts on your local computer, but publish them to WordPress.com. Import your WordPress.com reblogs. Always have a portable copy (a running copy) of your entire WordPress.com blog.