What is an IMDb Check In?

Today I noticed something that I don’t remember seeing before – IMDb movie pages now have a “Check In” button.  When clicked, a tiny form for comment is coming up, which also features some sort of sharing to Facebook.  The functionality is marked as beta, so I’m not sure who else can see it, how well it works, and what are the purposes of it at all.  Here are two screenshots – one of the button itself and another of the form which pops up when the button is clicked.

Do any of you guys see these?  Any idea what’s that and what is it for?  Have you seen any IMDb announcements about the feature or any blog posts in relation to this?