Overall I get the impression that it's not intended for the top dot to be used in all circumstances. When their use overbalances your main source of player aggro, perhaps lower level spells in the line are appropriate.
Downrank your DoTs if you find the new higher damage max level is too much aggro. The Aggro/damage hasn't changed just the ramp up speed.
In group content, Shaman's slow + two DOT aggro can now surpass a raid geared warrior's hate disc + button mashing + best aggro and/or DPS weapon(s), even when a shaman counts to Ten Mississippi before dropping the DOTs. That's without the use of Malo (low aggro but it adds up), spot heals, Cripple (now uncastable), or anything else that's fun like direct damage or melee. So cast your less good DOTs and pretend the DOT damage upgrade that was done to balance out DOT damage either never happened or was for invalid reasons. And whine on forums.