Tanks abilities (combos, Overpower and Flash) are very strong, so if you just happened to have competent (not even good but just decent) tanks during the beta, then it is understandable you never did.
From my position as tank in the beta I can say that keeping hate on a group of mobs wasn't hard, but it was about being careful and always keeping the threat up on those slept mobs mostly. Besides that, combos will keep the threat at the maximum level, and the only realistically way I see for someone stealing hate is through better gear (top decked out dps vs average geared tank).
Also with Provoke being such an amazing tool, there's no way that someone can take the focus of the tank for longer than a couple of seconds. Provoke puts the tank at the top of the thread list and if followed promptly by Flash and a combo, will put thinks back in order.
As a tank the biggest challenge is managing crowds, not single targets.
*Nods*
In part why I enjoyed tanking so much. Once I figured out my role, it was a fun challenge, and always kept me busy. It was a lot more rewarding than just spamming attacks 95% of the time as a DPS.
Also, in a half decent party, the tanks set the pace of the battle, which is nice. I hate guessing what others are going to do.