So, I thought I noticed this in the last snapshot but wasn't sure. I spent some time testing the issue a couple different ways this evening.
1. In survival mode, I found an existing NPC village and added several buildings with many doors (Mostly 4 x 4 with 8 doors). I took care to make sure that their 'cover' spaces were not overlapping. The villagers will walk around the village and even enter the new bulidings during daytime, but never show any interest in breeding. They never get any hearts or produce any new villager young.
2. In creative mode, I built two 6x6 buildings with 16 doors each for a total of 32 doors. The two are built diagonally from each other so as not to 'overlap' at all. Then I opened 2 villager eggs near by. The villagers will enter the buildings, but show no interest in each other. They don't get hearts or produce little villagers.
Villager breeding in 1.8 snapshots has been redone, and likely will continue to be tweaked. They no longer breed on their own, only when "in the mood" which a player can do by conducting trading with them. It isn't always a single trade, and you will need to do it with both villagers. So no automated breeding farms.