Don't worry.... You're not alone, i knda feel the same about my performance :S
I've noticed that my dps is lacking even when regarding the ilvl difference. I'm simming and optimizing quite a bit since the last raid. Try the simcraft tool, it's very usefull. I'm simming out on an avrg of 155k dps. I'm quite often a bit lower but the sim is based on a patchwork fight so getting that number without any encounter buff or lots of aoe seems impossible. It made me feel a little better about my dps at least.
Don't underestimate that we're still getting used to some encounters (a least us recruits in the guild) and that we're missing some pieces of gear that could make a huge difference (a decent weapon in my case, of which i got one last raid woot!). But myeah, I'm not sure either what gear will boost my dps enough to beat that damn gnoam monk of ours
Oh... If Luria is reading this: LAL!