Ok so I had my mage as frost for at least 50 lvl's easily bringing the most damage in groups I would run 90 percent of the time. From 68-70 I noticed that I had a lot more competition in the dsp/damage department, though most of time they were usually higher lvl or better geared. Anyways, I decided to try out switching to fire since it is the be all end all of raiding specs (2/48/11).
The jist of the thread is that upon changing spec and doing a instance I saw that my dps had dropped from a 3 run avg. of 712 dps down to 563 after a single run. Even if you take my lowest recorded dps as frost it is still 80 dps higher. Even my avg crit was higher as frost than as fire which doesn't make much sense. I know that my gear isn't the best and there needs to be a lot of improvement, but I don't see how there would be such a big drop in output.
Here is my armory http://www.wowarmory.com/character-sheet.xml?r=Proudmoore&n=Perkin
When I was attacking trash I started out just scorching then fire balling, but I noticed that mobs were dying faster that I could get all the scorches on so I started to just open fireballs and noticed an increase in dps.
My spell hit isn't capped so that might be a big part of it... Hopefully its something obvious.