I voted Moodlet but to be honest I shouldn't have voted for either. Some of them only add emotion and I would refer to those as moodlets, whereas others add not only emotion but also give extra effects (like skill gain boosts and whatnot) and those I would call buffs. I wasn't aware this was heavily debated.
I think referring to them all as buffs is silly though, because some of them add negative effects and in every video game I've ever played, a buff is something positive.