Games no longer end in ties unless both teams are on the same section of the unlocking process
Releasing a pair of fresh videos, Naughty Dog issued a new patch for The Last of Us along with Abandoned Territories Map Pack, the first DLC (downloadable content) for the game which contains four brand new multiplayer maps. Among other things, the patch adds DLC playlist for each game type - this includes both the retail maps and the DLC maps, but the DLC maps should appear much more frequently in the vote.
You can buy the Abandoned Territories Map Pack for $9.99 stand-alone - the map pack is also included in the $19.99 The Last of Us Season Pass. The Season Pass will be available for a limited time.