I can't find any real info on when to switch to DB, but I have to say you look good to my eyes (but I'd wait for Theo or Therion to chime in, unless you just want to go ahead and try it).
Just four notes (two of which you know):
1. Try and get a better weapon. DB is all about your MWD, so it being lower is not good. You're probably high enough to at least tie with Unholy though.
2. You could use a small bit more expertise. I believe something like 25-28 is the magic number for a DpS, which will push Dodge off the table, which is always nice. I think your hit could be slightly higher, too, but I'm not sure on that one (either way, you should be fine with both to go DB, they'll just boost DpS).
3. It seems you don't really need to worry about Armor Penetration. EJ seems to feel like the talents +Sunder/Expose are more than enough. Though, if gearing, Armor Pen > Haste.
4. Switch to the Sigil of the Dark Rider. Math says that yours only has a 5% uptime, where that one will add 90 damage to 8 strikes out of each rotation.
Other than that, make sure you have Glyph of Obliterate and Glyph of Blood Strike (which, apparently, also works for Blood Strike). At the moment, I would suggest Ghoul for the 3rd, considering Blood is a high Strength build, giving the ghoul an extra 40% is quite nice.
For minor glyphs, it is pretty much whatever you want. HoW is great. Raise Dead means you don't need Corpse Dust. Blood Tap means you no take damage (though you will probably make it back up in seconds with Blood Presence). The last real option is Death's Embrace, for when you are soloing an elite or something (or maybe saving your ghoul from an unfortunate double AoE hit, without sacrificing 40 RP).
Others know more about DB than me--this is just what I found at EJ, mixed with some opinion.
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IDrownFish wrote:
Anyways, you all are horrible, @#%^ed up people
lolgaxe wrote:
Never underestimate the healing power of a massive dong.