:/ well, that is your own call if you do not want to believe gameinformer.... but I do not think bethesda would have payed to advertise a feature that was not in the game...
Nothing about that in these videos:
http://www.g4tv.com/videos/59051/the-elder-scrolls-5-skyrim-dawnguard-extended-e3-gameplay-preview/
http://www.g4tv.com/videos/58929/the-elder-scrolls-v-skyrim-dawnguard-dlc-e3-gameplay-demo/
http://www.youtube.com/watch?v=Ux76mg7V4_o