Why did they take away vampire fangs?
For the beast races, it was likely because they saw some people complaining about the way they looked, so they removed them. For everyone else, probably time restraints. Either way, like I said before, it doesn't look as if it is going over too well. As a matter of fact, this subject is far more volatile than I imagined it would.
Anyway, for the record, I do feel like it was a slap in the face that they removed all the unique physical features of Argonian and Khajiit vampires and then replaced it with nothing. If they couldn't be bothered to do new assets for vampire Argonians and Khajiit due to time restraints, the least they could have done was leave their vanilla appearance alone for the most part, and maybe just tweak it so the Khajiit fur color doesn't fade like in vanilla. What they could do at the very least now is do the vampire eyes for the two races in a patch, and possibly the fangs as well. I don't expect them to do this, but it would cool things down a bit on the forums.