actually....
ive been trying out an ER build i saw on the Oboards. some 2k+ rated (in 3's) warrior (using swords no less) had a 44/14/3 build that included imp MS and ER.
and its actually not that bad. much better than when i was leveling from 60-70 anyway. however, i say this with only a low 1700's rating currently, as well as the caveat that youre on a team where you wont get attacked but rarely. my team setup is pally/war/lock or pally/priest/lock, so im almost always NOT the target. ER makes a big difference there. but on the rare occasion where i get focus fired (say, by a three dps team) then the lack of enrage really hurts. if youre getting attacked, then the +25% damage from enrage is pretty much always there, and that helps loads.
soon as i get up to the 1900 level ill let you guys know about my experiences there. i plan on getting to at least 1850 with this spec, but we'll see how it feels up there and whether or not ill keep it past that point.