I actually play with this some, even though I usually maintank, because I like big numbers, and talking trash to our dps that fall below me in dps on boss fights =P.
In my full tank kit, which can be viewed at
http://www.wowarmory.com/character-sheet.xml?r=Destromath&n=Scottzirra (if my fishing pole and goggles are on, it of course is not my standard gear) and full raid buffed, I push 2.2-2.4k dps on boss fights if I tank. I definitely clear 2k dps on most boss fights.
My current goal is to stack as much BV as i can which i estimate to be ~250BV using:
http://www.wowhead.com/?item=42987 which works out to ~190 constant str, or ~400 ap, ~100BV
There are several other upgrades that I have on a wish list, but the total gain from my gear to there is around 250BV.
The only slots left without BV on them are 1 trinket, and the shoulders.
Obviously the
http://www.wowhead.com/?item=40684 would be good, but
http://www.wowhead.com/?item=37872 could also be good.
Obviously some ret shoulders would fill the set out. However, until I drop the gear I can only speculate on what I suppose would be ideal.