Today's rumor is from Forgeworld staff at Games Day UK. I think he kind of slipped up on this question, because I am sure his answer should of been "The Forgeworld Teams are not working on one, I don't know about Games Workshops studios." Instead he indicated that "someone was working on them". Meaning Games Workshop has a model in the works. I know rumors have said that we would see one this fall, and many Space Wolf players were really looking forward to Games Day UK to see one.
Its only a small bit of info, but one that we all wanted to hear.
Tony was asked re Thunderwolves and his answer (to me at least) implied that FW weren't doing them but "someone" was. I'd guess a GW one is on the way.