[notout86]

I use TURTLE Wax Ice liquid wax T-468R and find that for the first 5 months or so, when wet spots are dry the dirt "sits up" on the paint and can be lightly dusted off. It is as though the dirt is repelled from the paint. Do not RUB at all as there is grit in the dirt.
Once the paint is dirty with oily water from the road, dusting is not enough and you have to wash but it comes off much more easily with that particular Turtle stuff.