One of the big problems with wow is that it's soloable. Hear me out before you decide this article is worthless. Because being a prot warrior is not soloable (Arms/Fury FTL), that makes tanks harder to find. No one wants to switch to Prot because the only use for Prot is soloing. A feral druid actually has fairly good DPS, a tankadin can tank/dps/heal to solo. Protection warriors really suck at battlegrounds and soloing. Why? No DPS. You can take all the hits in the world but NO dps.
Last night for the daily heroic there were seven DPS-specced warriors in the queue but no tanks to be seen. The solution? BALANCE the warrior class. Give Prot warriors DPS and make DPS warriors a viable tank solution. Give their attacks more agro and allow them to taunt their brains out. ANYTHING to increase the amount of tanks out there.
The addition of DeathKnight will be welcome in my opinion, however, the majority of DeathKnights out there will be DPS specced (AGAIN). Blizzard, if you read this (I doubt it) give us more TANKS!