Strange thing is that even though none of the games I've played in the previous 48 hours is on Bungie.net, my rank, which was changed to Sgt. last night is accurately reflected. Interestingly, when I checked now, the only game that's showing up since Thursday is a custom game from last night that has been "partially purged." This is what it says:
We�re sorry, this game has been partially purged. We periodically purge games of outdated or expired data, including the Game Viewer and other statistics.