WordPress 4.0, nicknamed ‘benny,’ was released a few days ago. I have not played with any of the new features: embeds or plugin finder. The editor appears to be the same despite the statements it should expand.
The auto updater for this site was disabled so I could manually verify plugins would work. The site database was also copied to another database in case the site needed to be restored.
The major change for this site involved the tying together the cookie and session. The XenWord plugin needs to be updated so nonce is not returning an obnoxious message when a XenForo user attempts to create and publish a WordPress post.
For now, this site includes a kludge to overcome posting a new WordPress post to the XenForo forum. Maybe a better fix will be found.