1. I personally don't think that dual wield is viable outside of Frost; you really need to go deep in frost to get Threat of Thassarian, otherwise you should just stick to 2handers
2. Glyphs: there's no reason to have glyph of scourge strike and glyph of obliterate... do one or the other.
3. I'm really not sure what you're doing with your spec in general, but there's a lot of things that kind of make me go "huh?" I haven't done unholy dps, but the 2 points in butchery seem wasted; I'm pretty sure the butchery ones would be better spent elsewhere (for ex: endless winter or black ice, especially if you're going to spec deeply into frost).
IMO: You don't go far enough frost to justify spending the points the way that you do; 3/5 Icy Talons isn't really getting you that much, and you skipped Black ice and endless winter, which are one of the better dps talents you could have gotten in frost
I suggest making a decision on whether to go dual wield, or 2hander, and if you want to dual wield you really should go with a frost spec rather than unholy. If dual wield, then look around for some spec info for dual wield frost. Elitist Jerks has some good info. They probably have good info on unholy as well. Make sure you read up enough so that you know why you're choosing each of your talents.
Keep in mind that frost is a more reactive spec than either of the other 2 dps specs, since you have to keep track of your procs (killing machine especially)
4. Gemming, this is a big problem for you. You have WAY too much hit, so those hit gems are wasted, agility is silly to gem for, you don't have the gems to activate your meta. I suggest regemming and just use 1 nightmare tear, in a blue gem slot for the socket bonus if you have one, and then otherwise just use inscribed ametrine (Str/Crit) if you're trying to match a yellow socket for the socket bonus and Bold cardinal ruby (Str) everywhere else. You're also missing a gem, and don't have a belt buckle in your belt.
5. Enchants; most of your gear is not enchanted. Get enchants on everything, and make sure you're getting the right enchants.
6. General Gear: Ditch the mark of supremacy, and run Heroic Forge of souls for the Needle encrusted scorpion.
For reference: I currently am dual wield frost dps on my DK (Darkalen), and I did a ~ 9.2k dps the last time I did Saurfang.