I’ve been on the PTR, but I don’t feel right about posting my results since I’m really not quite sure what spec or rotation is optimal for Frost quite yet. I will say that switching over to this spec and equipping two one-handers yielded about a 100 DPS loss on a dummy from 2h on live, using the ITx6 rotation. I predict that the winning rotation for Frost will be a dual-disease OB-centric one, because that’s where Blizz seems to want us and are clearly leading us in that direction.
Wild speculation and absolutely unreliable testing aside, I found out something rather interesting on the PTR this morning. If you’ve been using the ITx6 rotation, which often finds itself with 6 Death Runes, you will be pleased to hear that they’ve gotten smarter. Basically the deal used to be that if you used an ability that would consume a Death Rune (i.e. none of the basic rune available, such as a Blood Rune for Blood Strike) then Death Runes would be used from left to right, Blood first, then Unholy then Frost. This was problematic because we wanted our runes to refresh in U/F pairs for Obliterate rather than having two Unholy Runes up at once and no Frost.
What happens now is that your Death Runes remember which rune they actually are. What this means is that if you have 6 Death Runes available and cast a Plague Strike, it will use up an Unholy/Death Rune rather than the first rune available on the left. In addition, if you Obliterate with 6 Death Runes up, it will use one Unholy and one Frost rune, making it even simpler for you to refresh runes in pairs. Yay!