i find it odd on my server how the top warriors don't spec imp. slam. hmm.
anyway, you want to consider that you get more damage from white hits in dw fury than you do in a 2h arms spec. this is not the best example, but when i was in a 3man group with guildies in blade's edge to kill ogre elites, i doubled my MS warrior guildmate's total damage (80k to 40k), and i'm wearing mostly blues and he's got all blues and some arena/bg epics. as a 2h spec, you really need to spec 2/2 imp slam and bring all the haste trinkets/buffs you can find to a raid, even better if you have a shaman in the group.