Everyone needs help sometime or another, here's where you ask for it.
WHAT THIS IS NOT:
-Fix my spec plx???
-What is my next upgrade???
-What rotation should I use???
WHAT THIS IS:
-You have no clue why your (or someone elses) dps is so low
-You want to improve in general
-You are not satisfied with "Do X, Y, Z in that order" answers
-You want an answer better suited to your playstyle
WHAT WE NEED:
We can't help you if you don't help us. "I do 2500 dps in TOC25 HALP!" only shows us that you can't read this post. There are several tools out there that will help us analyze your output and thus be able to say exactly what the problem is. This is what you need to provide in your post.
Recommended: Combat Log Parse
The best way to review your output is to get a combat log parse so that we can see the complete picture. This will show not only what you did, when you did it, and how well you did it, but also what the entire raid did. Maybe the problem was that the Elemental Shaman and Ret Paladin always die really early, and therefore you were missing their combined buffs. A combat log parse will show this.
I recommend www.worldoflogs.com because of how easy their site is to navigate and how easy it is to run. It's very user friendly and has a lot of options and features. Once you have registered here and installed their client, the basic steps to create a combat log are:
1) Start the client
2) Follow these directions http://www.worldoflogs.com/help/client/ and start a "Live Report"
3) Open World of Warcraft, and when you're just about to start the fight, type /combatlog
4) When the boss is dead, type /combatlog again to stop
5) Switch back to the client and click "Sync Now" to send the report
6) Post that link here.
It's that simple.
Option Two: Recount Screenshot with Details
This won't show us all the details, but is better for anonymity of your guild mates. This is a bit simpler than the above because you should already know how to use Recount.
1) Kill the boss with Recount running
2) Pick that fight from the Recount window so we can filter out the rest of the crap
3) Click your name so the details appear
4) Hit print screen
5) Upload that image (World of Warcraft \ Screenshots \) to http://imageshack.us and post the link here. (You don't need a login here)
It should look like this
Last Ditch Effort: Recount or Combat Log Parse of Target Dummy
This should only be used as a last resort. Basically, follow the steps above but do so for a combat dummy.
Make sure that the target dummy has zero debuffs on it when you start, and you cast no debuffs on it. It needs to be 100% clean. We can take the numbers you show us and increase them as if you had full raid buffs. If you attack a dummy with a buff or two on it that you don't know about, we will inadvertently factor these buffs in twice, which will make us say "You should be doing XXXXX dps" when you physically can never reach this number.
If you are spec'd for Demonic Pact or Improved Shadow Bolt, say so in the parse so we can figure that out too.
DO NOT USE CURSE OF ELEMENTS. Use Doom or Agony on the dummy.