I am glad you posted this. I watched a replay of the game last night and started to open this same thread.
During quarters 1 - 3, he seemed to constantly talk about the Falcons. However, the Falcons were playing lights out!
During the 4 th quarter, he spoke about the Saints. If Vilma kept harping on the Falcons while the Falcons are loosing, that would be indicative of biases.
Vilma might also be worried that, he is too partial to his former team. He might be trying too hard to be impartial.