Facebook's ever evolving platform (Don't forget today's forced switch to Timeline.) is making a some new changes to Check-In. They're revising check-in numbers on Facebook Pages to offer a more accurate picture of how people are visiting your pages.
Among these changes, previously, if an individual checked into your page multiple times, each check-in was counted into your Page's total check-in number. Now, if someone checks into your page multiple times within a 12-hour period, that action will be counted as one unique check-in.
In addition, when people tag their friends at a location and upload a photo, those photo tags will be counted more holistically. For example, if 20 photos were uploaded to an album at a specific location, Facebook will now count that as a single check-in. If a fan checks into a location and tags five friends in the photo they uploads with their check-in, the total check-ins number will be six - the fan plus their 5 friends.