1. A method to identify a current user of a computing device, comprising: accessing a first cookie storage location of a first browser and a second cookie storage location of a second browser; locating a most recently used cookie from cookies stored in the first and the second cookie storage locations to identify a current usage activity associated with the computing device; parsing the most recently used cookie for an identifier; comparing the identifier to a cookie table, the cookie table associating cookies with panelists; when the identifier of the most recently used cookie is associated with one of the panelists, associating the current usage activity of the computing device with a corresponding panelist; and when the identifier of the most recently used cookie is not associated with any of the panelists, associating the current usage activity of the computing device with a guest.