Im looking for a way to use the Graph API to gather a list of users currently "checked in" to a particular place.
Any help is greatly appreciated!!!
To get a list of Users is not possible, because you'd then need the individual User's permission (respectively the Access Token) to access their checkin data (which I guess you don't have).
What you could is just to request the number of checkins on an hourly schedule with the mentioned FQL query. Then you could store/calculate this for yourself.
Use the following call: