Pingbacks have returned. If you've previously selected a setting, it will be the same; if you've never selected a setting, it will default to Open (on). You can change your setting here.
If you've been using the previous version of Facebook Connect, you'll need to reactivate your settings here.
I don't use facebook - it's presumably important or livejournal wouldn't have had this pop up as soon as I touched the site - so I've disabled it until I know.