What you guys need to understand is this vamplord some are being up in arms about aren't exactly described before, they aren't violating anything, no more than the Quad Tusked Mammoths or Mother wisps, relax...THAT ISN'T ALL THAT'S THERE.
As I've said before in other threads, it's not about the vampires themselves, but the message such decisions send.
Skyrim HAD vampires: the Volikhar. Come time for a TES title though, they're suddenly missing. Yes there's vampires named Volikhar, but they act nothing like them.
Meanwhile some strain of vampire that conveniently looks like vamps from a popular movie pop up, and these get their own DLC.
It's called selling out. The existing TES lore is being neglected whereas an idea perceived to be popular with the general population is being forced into TES with a crowbar.