Remember how Bungie told us they had advanced algorithms to seperate DLC players from non-DLC players in existing playlists?
Well I got this from the noble map pack thingy on bungie.net:

"Many other playlists will contain DLC maps as well, but since you are not gated from entry to these playlists by having DLC, you could match with people who don’t have the maps. If that happens, you will not get them as voting options for that session."

Epic lies of bungie?