Just prior to 3.3 going live, the theorycrafters were suggesting the glyphs best used by Unholy dps DKs would be Icy Touch, Dark Death, and Ghoul.
Once live hit, it became apparent just how powerful the new Scourge Strike is (unfortunately, this has lead to rampant speculation that a nerf is incoming). As such, Consider's wonderful thread on unholy dps has concluded that we DO need to use Glyph of Disease instead of Dark Death.
I previously mentioned that it's no longer possible to 'roll diseases.' In 3.2, pestilence refreshed your diseases at your original attack power - for me this was typically around 11-12k. This was too powerful, so in 3.3 Blizzard changed it. Glyph of Disease now allows you to refresh your diseases on your primary target (saving you a frost and unholy rune), but at your current attack power. Nonetheless, on live GOD is still worth using apparently. This is because saving the FU runes allows one more Scourge Strike in the rotation, which is tremendously powerful right now.
Tonight I'll grab a GOD and replace the Dark Death one I have.
Unfortunately my ability to do live testing of these specs is seriously hampered by the fact that I'm not doing 25 man raids right now. The late night remnants of Fallout on the new server only has enough people to partially fill a 10-man and we're filling the holes with the new guildies or their alts. Not really conducive to testing. I'm pleased with my performance thus far, but it's difficult to say how the new 17/0/54 compares to other specs for now. On the other hand, I'm seeing posts in both the blood and frost threads on EJ from DKs proclaiming that unholy is the 'only' way to go right now... time will tell.
One other side note: FOR ONCE I'm growing convinced that the theorycrafters are right about starting with PS>IT>BS>SS>BS and so on instead of starting with an Icy Touch.
Why? It's a little complex, but apparently saving the cooldown when using Icy Touch from range isn't nearly as valuable as applying your diseases - and refreshing them - with Rage of Rivendare. While pestilence-refreshing uses your current ap, it relies on the original yes/no for having blood plague up. So, the end result is that if you IT before PS, you'll refresh disease without a Rage of Rivendare-buffed frost fever.
Obtuse? Yes. Silly. For sure. But, in any case, for now I'll be Death Coiling as I run in, then going Plague Strike > Icy Touch.