There are a whole load of new changes (22, to be exact) but a few of them really stand out. There's quite a bit of Blood love to try and make the spec more desirable at the endgame, one change being Heart Strike. While keeping its cost of one Blood Rune, it acts like a Cleave instead of a Haste debuff. It still hits harder than Blood Strike, too. That's pretty awesome!
One thing I personally don't see as a good change is switching Corpse Explosion to Runic Power, off of an Unholy Rune. Maybe I'm doing something wrong, but on my Unholy Death Knight I never seem to have enough Runic Power to use the abilities I want to use, and this won't help that. Of course, I don't have any spare Unholy Runes either. Maybe the spec needs some Runic Power generation love someday. To see the full list of changes, click through the link below.