In my experience, it can vary wildy depending upon what is going on with their systems.
They endeavor to respond within 24 hours, and when things are seriously borken for a lot of users, and the support queue is high, it can take that long or longer.
Other times, when things are running generally well, and the support queue is low, I've had responses in less than 5 minutes,
I suspect the panel problems, and fallout from the things listed on dreamhoststatus.com, might mean that they have a fairly good size queue going at present.
Hopefully, they will get to your ticket sooner rather than later!.