I suddenly was just thinking of one question posted earlier this week regarding waxing a new car. This is what I know:
For a brand new car, it is all right to immediately wax it since the painting process includes baking the paint until it is "fully cured".
However, if you ever have to repaint the car, do not wax that part for several months. The reason for this is because body shop can not bake the paint and cure it completely since they can't bake too hot (otherwise it will ruin your car since usually they bake the whole car unless it is a bumper). Even if they can take the panel apart, usually they won't bother to "cure" the paint completely.
This way, you will still have some solvents in the paint and waxing it will seal off the pores, not allowing the solvent to evaporate (i.e. cure). In the long run, this will lead to discoloration and shading of the painted parts.
Hope this helps.