First I thought it was a client-side issue, but others have commented on it too and have had it happen when they are grouped (group members can't see the mistform player).
Has anybody else noticed that when a vampire enters mist form, he turns completely invisible and can't be detected until he steps out of the cloud? There used to be a floating cloudy thing going on, but now there's nothing, no visual cues at all.
Is it just my client, my skills or my eyes, or does this really happen? Perhaps they were using nightblade invisibility skill instead, although I think the animation was cloud transformation.