Thoughts coming soon... but I'm kind of confused as to why this would be added to core when it's ... already always included with any install... and no one uses it... and post types are going away... and the end user experience with the whole thing is conflated and annoying anyway. Unless your Matt Mullenweg who has a really slick blog but then you'd expect Matt to have a slick blog that works well with CPT's and the PressThis bookmarklet....

But I digress.....