One facebook item updating at each cron run

The "Recent log entries" report is showing that one particular facebook status is updating every time cron runs. It is not my most recent facebook update -- activity stream has collected several since. The item that is constantly updating is a little on the long side: 326 characters (not counting my username and a space appearing before the status update).

If this were happening with a lot of items or for a lot of users, it seems like it could be a resource drain.