As you get higher level it's much easier to hold AoE aggro as a tank, as a monk you get a couple of abilities.
Keg Smash should be used on cooldown, it does splash AoE damage, and at lvl 40 you get Breath of Fire.
It's not until level 60 where you get a talent to summon a statue that aoe pulse taunts, and then the real easy mode abiltity is Rushing Jade Wind at lvl 90. It's literally just aoe damage circling around you constantly. It doesn't hit for a lot but it keeps aggro without even thinking about it.
At level 40 your hunters also get an ability called Misdirect, you'll want to throw this on your tank and it makes their aggro go to the tank for 10 seconds. Making it even easier.

I'd say for now it's gonna be slightly tough but it does get easier to the point where it doesn't really become an issue down the road.
This applies for all tanks, they'll get some form of aoe taunt/damage.