I don't think this is true anymore. According to this article, Dubai now has a sewage system covering the entire city: http://p4papyrus.blogspot.ca/2011/02/sewage-system-now-cover...

As a former resident and that I still go through quite often, some limited high-end parts of the city have central sewage but the broad majority of sewage is still trucked from individual buildings to the treatment plants.

Is there a proper address system yet?

There is in the diplomatic area. There's been talk in the papers about proper addresses being rolled out sometime soon but I imagine the squabbling over naming rights for the roads will take a while to sort out.