Inhaling plant matter in general is not good for the lungs. I cannot speak to damaging the cilia, but I believe that would be a result from having smoke in your lungs period. There are carcinogens in weed just as there are in tobacco. There may be some worse ones in tobacco, but that doesnt mean marijuana smoking wont harm or damage the functionality of the lungs.
Vaporizing definitely helps eliminate majority of the carcinogens but I still think it could have minor adverse effects as far as mucus production.
When you smoke, mucus coats the alveolar cells in your lungs (where gas exchange occurs). This happens from marijuana + tobacco smoke. this means that your lungs need to work harder to achieve the proper levels of O2 exchange, which puts a strain on the diaphragm muscle and forces you to use accessory muscles for breathing.
I personally prefer vaporization knowing the kind of damage that occurs in the lungs and vaporization minimizes these effects.