I would love it.
Facebook becomes more and more boring the latest years, because they don’t showing anything like that. The newsfeed isn’t as much interesting like any of my discourse communities I’m in. Overall they recently kicked out the plugin support for www.sadlyunfriended.com – They informed me at least about cancelled friendships via email who and when. This was pretty great.
Back to Discourse: Viewing (by myself) who visited my profile page and (publicly visible) how many people, would be a killer feature 